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Functions for working with dates and times

Most functions in this section accept an optional time zone argument, e.g. Europe/Amsterdam. In this case, the time zone is the specified one instead of the local (default) one.

Example

makeDate

Creates a Date

  • from a year, month and day argument, or
  • from a year and day of year argument.

Syntax

Alias:

  • MAKEDATE(year, month, day);
  • MAKEDATE(year, day_of_year);

Arguments

Returned value

  • A date created from the arguments. Date.

Example

Create a Date from a year, month and day:

Result:

Create a Date from a year and day of year argument:

Result:

makeDate32

Creates a date of type Date32 from a year, month, day (or optionally a year and a day).

Syntax

Arguments

Note

If month is omitted then day should take a value between 1 and 365, otherwise it should take a value between 1 and 31.

Returned values

  • A date created from the arguments. Date32.

Examples

Create a date from a year, month, and day:

Query:

Result:

Create a Date from a year and day of year:

Query:

Result:

makeDateTime

Creates a DateTime from a year, month, day, hour, minute and second argument.

Syntax

Arguments

Returned value

  • A date with time created from the arguments. DateTime.

Example

Result:

makeDateTime64

Creates a DateTime64 data type value from its components: year, month, day, hour, minute, second. With optional sub-second precision.

Syntax

Arguments

Returned value

  • A date and time created from the supplied arguments. DateTime64.

Example

timestamp

Converts the first argument 'expr' to type DateTime64(6). If a second argument 'expr_time' is provided, it adds the specified time to the converted value.

Syntax

Alias: TIMESTAMP

Arguments

  • expr - Date or date with time. String.
  • expr_time - Optional parameter. Time to add. String.

Examples

Result:

Result:

Returned value

timeZone

Returns the timezone of the current session, i.e. the value of setting session_timezone. If the function is executed in the context of a distributed table, then it generates a normal column with values relevant to each shard, otherwise it produces a constant value.

Syntax

Alias: timezone.

Returned value

Example

Result:

See also

serverTimeZone

Returns the timezone of the server, i.e. the value of setting timezone. If the function is executed in the context of a distributed table, then it generates a normal column with values relevant to each shard. Otherwise, it produces a constant value.

Syntax

Alias: serverTimezone.

Returned value

Example

Result:

See also

toTimeZone

Converts a date or date with time to the specified time zone. Does not change the internal value (number of unix seconds) of the data, only the value's time zone attribute and the value's string representation changes.

Syntax

Alias: toTimezone.

Arguments

  • value — Time or date and time. DateTime64.
  • timezone — Timezone for the returned value. String. This argument is a constant, because toTimezone changes the timezone of a column (timezone is an attribute of DateTime* types).

Returned value

Example

Result:

See Also

timeZoneOf

Returns the timezone name of DateTime or DateTime64 data types.

Syntax

Alias: timezoneOf.

Arguments

Returned value

Example

Result:

timeZoneOffset

Returns the timezone offset in seconds from UTC. The function daylight saving time and historical timezone changes at the specified date and time into account. The IANA timezone database is used to calculate the offset.

Syntax

Alias: timezoneOffset.

Arguments

Returned value

  • Offset from UTC in seconds. Int32.

Example

Result:

toYear

Returns the year component (AD) of a date or date with time.

Syntax

Alias: YEAR

Arguments

Returned value

  • The year of the given date/time. UInt16.

Example

Result:

toQuarter

Returns the quarter (1-4) of a date or date with time.

Syntax

Alias: QUARTER

Arguments

Returned value

  • The quarter of the year (1, 2, 3 or 4) of the given date/time. UInt8.

Example

Result:

toMonth

Returns the month component (1-12) of a date or date with time.

Syntax

Alias: MONTH

Arguments

Returned value

  • The month of the year (1 - 12) of the given date/time. UInt8.

Example

Result:

toDayOfYear

Returns the number of the day within the year (1-366) of a date or date with time.

Syntax

Alias: DAYOFYEAR

Arguments

Returned value

  • The day of the year (1 - 366) of the given date/time. UInt16.

Example

Result:

toDayOfMonth

Returns the number of the day within the month (1-31) of a date or date with time.

Syntax

Aliases: DAYOFMONTH, DAY

Arguments

Returned value

  • The day of the month (1 - 31) of the given date/time. UInt8.

Example

Result:

toDayOfWeek

Returns the number of the day within the week of a date or date with time.

The two-argument form of toDayOfWeek() enables you to specify whether the week starts on Monday or Sunday, and whether the return value should be in the range from 0 to 6 or 1 to 7. If the mode argument is omitted, the default mode is 0. The time zone of the date can be specified as the third argument.

ModeFirst day of weekRange
0Monday1-7: Monday = 1, Tuesday = 2, ..., Sunday = 7
1Monday0-6: Monday = 0, Tuesday = 1, ..., Sunday = 6
2Sunday0-6: Sunday = 0, Monday = 1, ..., Saturday = 6
3Sunday1-7: Sunday = 1, Monday = 2, ..., Saturday = 7

Syntax

Alias: DAYOFWEEK.

Arguments

  • t - a Date, Date32, DateTime or DateTime64
  • mode - determines what the first day of the week is. Possible values are 0, 1, 2 or 3. See the table above for the differences.
  • timezone - optional parameter, it behaves like any other conversion function

The first argument can also be specified as String in a format supported by parseDateTime64BestEffort(). Support for string arguments exists only for reasons of compatibility with MySQL which is expected by certain 3rd party tools. As string argument support may in future be made dependent on new MySQL-compatibility settings and because string parsing is generally slow, it is recommended to not use it.

Returned value

  • The day of the week (1-7), depending on the chosen mode, of the given date/time

Example

The following date is April 21, 2023, which was a Friday:

Result:

toHour

Returns the hour component (0-24) of a date with time.

Assumes that if clocks are moved ahead, it is by one hour and occurs at 2 a.m., and if clocks are moved back, it is by one hour and occurs at 3 a.m. (which is not always exactly when it occurs - it depends on the timezone).

Syntax

Alias: HOUR

Arguments

Returned value

  • The hour of the day (0 - 23) of the given date/time. UInt8.

Example

Result:

toMinute

Returns the minute component (0-59) a date with time.

Syntax

Alias: MINUTE

Arguments

Returned value

  • The minute of the hour (0 - 59) of the given date/time. UInt8.

Example

Result:

toSecond

Returns the second component (0-59) of a date with time. Leap seconds are not considered.

Syntax

Alias: SECOND

Arguments

Returned value

  • The second in the minute (0 - 59) of the given date/time. UInt8.

Example

Result:

toMillisecond

Returns the millisecond component (0-999) of a date with time.

Syntax

Arguments*

Alias: MILLISECOND

Result:

Returned value

  • The millisecond in the minute (0 - 59) of the given date/time. UInt16.

toUnixTimestamp

Converts a string, a date or a date with time to the Unix Timestamp in UInt32 representation.

If the function is called with a string, it accepts an optional timezone argument.

Syntax

Returned value

  • Returns the unix timestamp. UInt32.

Example

Result:

Note

The return type of toStartOf*, toLastDayOf*, toMonday, timeSlot functions described below is determined by the configuration parameter enable_extended_results_for_datetime_functions which is 0 by default.

Behavior for

  • enable_extended_results_for_datetime_functions = 0:
    • Functions toStartOfYear, toStartOfISOYear, toStartOfQuarter, toStartOfMonth, toStartOfWeek, toLastDayOfWeek, toLastDayOfMonth, toMonday return Date or DateTime.
    • Functions toStartOfDay, toStartOfHour, toStartOfFifteenMinutes, toStartOfTenMinutes, toStartOfFiveMinutes, toStartOfMinute, timeSlot return DateTime. Though these functions can take values of the extended types Date32 and DateTime64 as an argument, passing them a time outside the normal range (year 1970 to 2149 for Date / 2106 for DateTime) will produce wrong results.
  • enable_extended_results_for_datetime_functions = 1:
    • Functions toStartOfYear, toStartOfISOYear, toStartOfQuarter, toStartOfMonth, toStartOfWeek, toLastDayOfWeek, toLastDayOfMonth, toMonday return Date or DateTime if their argument is a Date or DateTime, and they return Date32 or DateTime64 if their argument is a Date32 or DateTime64.
    • Functions toStartOfDay, toStartOfHour, toStartOfFifteenMinutes, toStartOfTenMinutes, toStartOfFiveMinutes, toStartOfMinute, timeSlot return DateTime if their argument is a Date or DateTime, and they return DateTime64 if their argument is a Date32 or DateTime64.

toStartOfYear

Rounds down a date or date with time to the first day of the year. Returns the date as a Date object.

Syntax

Arguments

Returned value

  • The first day of the year of the input date/time. Date.

Example

Result:

toStartOfISOYear

Rounds down a date or date with time to the first day of the ISO year, which can be different than a "regular" year. (See https://en.wikipedia.org/wiki/ISO_week_date.)

Syntax

Arguments

Returned value

  • The first day of the year of the input date/time. Date.

Example

Result:

toStartOfQuarter

Rounds down a date or date with time to the first day of the quarter. The first day of the quarter is either 1 January, 1 April, 1 July, or 1 October. Returns the date.

Syntax

Arguments

Returned value

  • The first day of the quarter of the given date/time. Date.

Example

Result:

toStartOfMonth

Rounds down a date or date with time to the first day of the month. Returns the date.

Syntax

Arguments

Returned value

  • The first day of the month of the given date/time. Date.

Example

Result:

Note

The behavior of parsing incorrect dates is implementation specific. ClickHouse may return zero date, throw an exception, or do "natural" overflow.

toLastDayOfMonth

Rounds a date or date with time to the last day of the month. Returns the date.

Syntax

Alias: LAST_DAY

Arguments

Returned value

  • The last day of the month of the given date/time=. Date.

Example

Result:

toMonday

Rounds down a date or date with time to the nearest Monday. Returns the date.

Syntax

Arguments

Returned value

  • The date of the nearest Monday on or prior to the given date. Date.

Example

Result:

toStartOfWeek

Rounds a date or date with time down to the nearest Sunday or Monday. Returns the date. The mode argument works exactly like the mode argument in function toWeek(). If no mode is specified, it defaults to 0.

Syntax

Arguments

  • t - a Date, Date32, DateTime or DateTime64
  • mode - determines the first day of the week as described in the toWeek() function
  • timezone - Optional parameter, it behaves like any other conversion function

Returned value

  • The date of the nearest Sunday or Monday on or prior to the given date, depending on the mode. Date.

Example

Result:

toLastDayOfWeek

Rounds a date or date with time up to the nearest Saturday or Sunday. Returns the date. The mode argument works exactly like the mode argument in function toWeek(). If no mode is specified, mode is assumed as 0.

Syntax

Arguments

  • t - a Date, Date32, DateTime or DateTime64
  • mode - determines the last day of the week as described in the toWeek function
  • timezone - Optional parameter, it behaves like any other conversion function

Returned value

  • The date of the nearest Sunday or Monday on or after the given date, depending on the mode. Date.

Example

Result:

toStartOfDay

Rounds down a date with time to the start of the day.

Syntax

Arguments

Returned value

  • The start of the day of the given date/time. DateTime.

Example

Result:

toStartOfHour

Rounds down a date with time to the start of the hour.

Syntax

Arguments

Returned value

  • The start of the hour of the given date/time. DateTime.

Example

Result:

toStartOfMinute

Rounds down a date with time to the start of the minute.

Syntax

Arguments

Returned value

  • The start of the minute of the given date/time. DateTime.

Example

Result:

toStartOfSecond

Truncates sub-seconds.

Syntax

Arguments

  • value — Date and time. DateTime64.
  • timezoneTimezone for the returned value (optional). If not specified, the function uses the timezone of the value parameter. String.

Returned value

Examples

Query without timezone:

Result:

Query with timezone:

Result:

See also

  • Timezone server configuration parameter.

toStartOfMillisecond

Rounds down a date with time to the start of the milliseconds.

Syntax

Arguments

  • value — Date and time. DateTime64.
  • timezoneTimezone for the returned value (optional). If not specified, the function uses the timezone of the value parameter. String.

Returned value

Examples

Query without timezone:

Result:

Query with timezone:

Result:

toStartOfMicrosecond

Rounds down a date with time to the start of the microseconds.

Syntax

Arguments

  • value — Date and time. DateTime64.
  • timezoneTimezone for the returned value (optional). If not specified, the function uses the timezone of the value parameter. String.

Returned value

Examples

Query without timezone:

Result:

Query with timezone:

Result:

See also

  • Timezone server configuration parameter.

toStartOfNanosecond

Rounds down a date with time to the start of the nanoseconds.

Syntax

Arguments

  • value — Date and time. DateTime64.
  • timezoneTimezone for the returned value (optional). If not specified, the function uses the timezone of the value parameter. String.

Returned value

Examples

Query without timezone:

Result:

Query with timezone:

Result:

See also

  • Timezone server configuration parameter.

toStartOfFiveMinutes

Rounds down a date with time to the start of the five-minute interval.

Syntax

Arguments

Returned value

  • The start of the five-minute interval of the given date/time. DateTime.

Example

Result:

toStartOfTenMinutes

Rounds down a date with time to the start of the ten-minute interval.

Syntax

Arguments

Returned value

  • The start of the ten-minute interval of the given date/time. DateTime.

Example

Result:

toStartOfFifteenMinutes

Rounds down the date with time to the start of the fifteen-minute interval.

Syntax

Arguments

Returned value

  • The start of the fifteen-minute interval of the given date/time. DateTime.

Example

Result:

toStartOfInterval

This function generalizes other toStartOf*() functions with toStartOfInterval(date_or_date_with_time, INTERVAL x unit [, time_zone]) syntax. For example,

  • toStartOfInterval(t, INTERVAL 1 YEAR) returns the same as toStartOfYear(t),
  • toStartOfInterval(t, INTERVAL 1 MONTH) returns the same as toStartOfMonth(t),
  • toStartOfInterval(t, INTERVAL 1 DAY) returns the same as toStartOfDay(t),
  • toStartOfInterval(t, INTERVAL 15 MINUTE) returns the same as toStartOfFifteenMinutes(t).

The calculation is performed relative to specific points in time:

IntervalStart
YEARyear 0
QUARTER1900 Q1
MONTH1900 January
WEEK1970, 1st week (01-05)
DAY1970-01-01
HOUR(*)
MINUTE1970-01-01 00:00:00
SECOND1970-01-01 00:00:00
MILLISECOND1970-01-01 00:00:00
MICROSECOND1970-01-01 00:00:00
NANOSECOND1970-01-01 00:00:00

(*) hour intervals are special: the calculation is always performed relative to 00:00:00 (midnight) of the current day. As a result, only hour values between 1 and 23 are useful.

If unit WEEK was specified, toStartOfInterval assumes that weeks start on Monday. Note that this behavior is different from that of function toStartOfWeek in which weeks start by default on Sunday.

Syntax

Aliases: time_bucket, date_bin.

The second overload emulates TimescaleDB's time_bucket() function, respectively PostgreSQL's date_bin() function, e.g.

Result:

See Also

toTimeWithFixedDate

Converts a date with time to a certain fixed date, while preserving the time.

Syntax

Alias: toTime - can be used only when the use_legacy_to_time setting is enabled.

Arguments

Returned value

  • DateTime with date equated to 1970-01-02 while preserving the time. DateTime.
Note

If the date input argument contained sub-second components, they will be dropped in the returned DateTime value with second-accuracy.

Example

Query:

Result:

toRelativeYearNum

Converts a date, or date with time, to the number of years elapsed since a certain fixed point in the past.

Syntax

Arguments

Returned value

  • The number of years from a fixed reference point in the past. UInt16.

Example

Query:

Result:

toRelativeQuarterNum

Converts a date, or date with time, to the number of quarters elapsed since a certain fixed point in the past.

Syntax

Arguments

Returned value

  • The number of quarters from a fixed reference point in the past. UInt32.

Example

Query:

Result:

toRelativeMonthNum

Converts a date, or date with time, to the number of months elapsed since a certain fixed point in the past.

Syntax

Arguments

Returned value

  • The number of months from a fixed reference point in the past. UInt32.

Example

Query:

Result:

toRelativeWeekNum

Converts a date, or date with time, to the number of weeks elapsed since a certain fixed point in the past.

Syntax

Arguments

Returned value

  • The number of weeks from a fixed reference point in the past. UInt32.

Example

Query:

Result:

toRelativeDayNum

Converts a date, or date with time, to the number of days elapsed since a certain fixed point in the past.

Syntax

Arguments

Returned value

  • The number of days from a fixed reference point in the past. UInt32.

Example

Query:

Result:

toRelativeHourNum

Converts a date, or date with time, to the number of hours elapsed since a certain fixed point in the past.

Syntax

Arguments

Returned value

  • The number of hours from a fixed reference point in the past. UInt32.

Example

Query:

Result:

toRelativeMinuteNum

Converts a date, or date with time, to the number of minutes elapsed since a certain fixed point in the past.

Syntax

Arguments

Returned value

  • The number of minutes from a fixed reference point in the past. UInt32.

Example

Query:

Result:

toRelativeSecondNum

Converts a date, or date with time, to the number of the seconds elapsed since a certain fixed point in the past.

Syntax

Arguments

Returned value

  • The number of seconds from a fixed reference point in the past. UInt32.

Example

Query:

Result:

toISOYear

Converts a date, or date with time, to the ISO year as a UInt16 number.

Syntax

Arguments

Returned value

  • The input value converted to a ISO year number. UInt16.

Example

Query:

Result:

toISOWeek

Converts a date, or date with time, to a UInt8 number containing the ISO Week number.

Syntax

Arguments

  • value — The value with date or date with time.

Returned value

  • value converted to the current ISO week number. UInt8.

Example

Query:

Response:

toWeek

This function returns the week number for date or datetime. The two-argument form of toWeek() enables you to specify whether the week starts on Sunday or Monday and whether the return value should be in the range from 0 to 53 or from 1 to 53. If the mode argument is omitted, the default mode is 0.

toISOWeek() is a compatibility function that is equivalent to toWeek(date,3).

The following table describes how the mode argument works.

ModeFirst day of weekRangeWeek 1 is the first week ...
0Sunday0-53with a Sunday in this year
1Monday0-53with 4 or more days this year
2Sunday1-53with a Sunday in this year
3Monday1-53with 4 or more days this year
4Sunday0-53with 4 or more days this year
5Monday0-53with a Monday in this year
6Sunday1-53with 4 or more days this year
7Monday1-53with a Monday in this year
8Sunday1-53contains January 1
9Monday1-53contains January 1

For mode values with a meaning of "with 4 or more days this year," weeks are numbered according to ISO 8601:1988:

  • If the week containing January 1 has 4 or more days in the new year, it is week 1.

  • Otherwise, it is the last week of the previous year, and the next week is week 1.

For mode values with a meaning of "contains January 1", the week contains January 1 is week 1. It does not matter how many days in the new year the week contained, even if it contained only one day. I.e. if the last week of December contains January 1 of the next year, it will be week 1 of the next year.

Syntax

Alias: WEEK

Arguments

  • t – Date or DateTime.
  • mode – Optional parameter, Range of values is [0,9], default is 0.
  • Timezone – Optional parameter, it behaves like any other conversion function.

The first argument can also be specified as String in a format supported by parseDateTime64BestEffort(). Support for string arguments exists only for reasons of compatibility with MySQL which is expected by certain 3rd party tools. As string argument support may in future be made dependent on new MySQL-compatibility settings and because string parsing is generally slow, it is recommended to not use it.

Example

toYearWeek

Returns year and week for a date. The year in the result may be different from the year in the date argument for the first and the last week of the year.

The mode argument works like the mode argument to toWeek(). For the single-argument syntax, a mode value of 0 is used.

toISOYear() is a compatibility function that is equivalent to intDiv(toYearWeek(date,3),100).

Caution

The week number returned by toYearWeek() can be different from what the toWeek() returns. toWeek() always returns week number in the context of the given year, and in case toWeek() returns 0, toYearWeek() returns the value corresponding to the last week of previous year. See prev_yearWeek in example below.

Syntax

Alias: YEARWEEK

The first argument can also be specified as String in a format supported by parseDateTime64BestEffort(). Support for string arguments exists only for reasons of compatibility with MySQL which is expected by certain 3rd party tools. As string argument support may in future be made dependent on new MySQL-compatibility settings and because string parsing is generally slow, it is recommended to not use it.

Example

toDaysSinceYearZero

Returns for a given date, the number of days passed since 1 January 0000 in the proleptic Gregorian calendar defined by ISO 8601. The calculation is the same as in MySQL's TO_DAYS() function.

Syntax

Alias: TO_DAYS

Arguments

  • date — The date to calculate the number of days passed since year zero from. Date, Date32, DateTime or DateTime64.
  • time_zone — A String type const value or an expression represent the time zone. String types

Returned value

The number of days passed since date 0000-01-01. UInt32.

Example

Result:

See Also

fromDaysSinceYearZero

Returns for a given number of days passed since 1 January 0000 the corresponding date in the proleptic Gregorian calendar defined by ISO 8601. The calculation is the same as in MySQL's FROM_DAYS() function.

The result is undefined if it cannot be represented within the bounds of the Date type.

Syntax

Alias: FROM_DAYS

Arguments

  • days — The number of days passed since year zero.

Returned value

The date corresponding to the number of days passed since year zero. Date.

Example

Result:

See Also

fromDaysSinceYearZero32

Like fromDaysSinceYearZero but returns a Date32.

age

Returns the unit component of the difference between startdate and enddate. The difference is calculated using a precision of 1 nanosecond. E.g. the difference between 2021-12-29 and 2022-01-01 is 3 days for day unit, 0 months for month unit, 0 years for year unit.

For an alternative to age, see function date_diff.

Syntax

Arguments

  • unit — The type of interval for result. String. Possible values:

    • nanosecond, nanoseconds, ns
    • microsecond, microseconds, us, u
    • millisecond, milliseconds, ms
    • second, seconds, ss, s
    • minute, minutes, mi, n
    • hour, hours, hh, h
    • day, days, dd, d
    • week, weeks, wk, ww
    • month, months, mm, m
    • quarter, quarters, qq, q
    • year, years, yyyy, yy
  • startdate — The first time value to subtract (the subtrahend). Date, Date32, DateTime or DateTime64.

  • enddate — The second time value to subtract from (the minuend). Date, Date32, DateTime or DateTime64.

  • timezoneTimezone name (optional). If specified, it is applied to both startdate and enddate. If not specified, timezones of startdate and enddate are used. If they are not the same, the result is unspecified. String.

Returned value

Difference between enddate and startdate expressed in unit. Int.

Example

Result:

Result:

date_diff

Returns the count of the specified unit boundaries crossed between the startdate and the enddate. The difference is calculated using relative units, e.g. the difference between 2021-12-29 and 2022-01-01 is 3 days for unit day (see toRelativeDayNum), 1 month for unit month (see toRelativeMonthNum) and 1 year for unit year (see toRelativeYearNum).

If unit week was specified, date_diff assumes that weeks start on Monday. Note that this behavior is different from that of function toWeek() in which weeks start by default on Sunday.

For an alternative to date_diff, see function age.

Syntax

Aliases: dateDiff, DATE_DIFF, timestampDiff, timestamp_diff, TIMESTAMP_DIFF.

Arguments

  • unit — The type of interval for result. String. Possible values:

    • nanosecond, nanoseconds, ns
    • microsecond, microseconds, us, u
    • millisecond, milliseconds, ms
    • second, seconds, ss, s
    • minute, minutes, mi, n
    • hour, hours, hh, h
    • day, days, dd, d
    • week, weeks, wk, ww
    • month, months, mm, m
    • quarter, quarters, qq, q
    • year, years, yyyy, yy
  • startdate — The first time value to subtract (the subtrahend). Date, Date32, DateTime or DateTime64.

  • enddate — The second time value to subtract from (the minuend). Date, Date32, DateTime or DateTime64.

  • timezoneTimezone name (optional). If specified, it is applied to both startdate and enddate. If not specified, timezones of startdate and enddate are used. If they are not the same, the result is unspecified. String.

Returned value

Difference between enddate and startdate expressed in unit. Int.

Example

Result:

Result:

date_trunc

Truncates date and time data to the specified part of date.

Syntax

Alias: dateTrunc.

Arguments

  • unit — The type of interval to truncate the result. String Literal. Possible values:

    • nanosecond - Compatible only with DateTime64
    • microsecond - Compatible only with DateTime64
    • millisecond - Compatible only with DateTime64
    • second
    • minute
    • hour
    • day
    • week
    • month
    • quarter
    • year

    unit argument is case-insensitive.

  • value — Date and time. Date, Date32, DateTime or DateTime64.

  • timezoneTimezone name for the returned value (optional). If not specified, the function uses the timezone of the value parameter. String.

Returned value

If the unit argument is Year, Quarter, Month, or Week,

  • and the value argument is Date32 or DateTime64, then Date32 is returned,
  • otherwise, Date is returned.

If the unit argument is Day, Hour, Minute, or Second,

  • and the value argument is Date32 or DateTime64, then DateTime64 is returned,
  • otherwise, DateTime is returned.

If the unit argument is Millisecond, Microsecond, or Nanosecond, then DateTime64 with scale 3 or 6 or 9 (depending on the unit argument) is returned.

Example

Query without timezone:

Result:

Query with the specified timezone:

Result:

See Also

date_add

Adds the time interval or date interval to the provided date or date with time.

If the addition results in a value outside the bounds of the data type, the result is undefined.

Syntax

Alternative syntax:

Aliases: dateAdd, DATE_ADD.

Arguments

  • unit — The type of interval to add. Note: This is not a String and must therefore not be quoted. Possible values:

    • second
    • minute
    • hour
    • day
    • week
    • month
    • quarter
    • year
  • value — Value of interval to add. Int.

  • date — The date or date with time to which value is added. Date, Date32, DateTime or DateTime64.

Returned value

Date or date with time obtained by adding value, expressed in unit, to date. Date, Date32, DateTime or DateTime64.

Example

Result:

Result:

See Also

date_sub

Subtracts the time interval or date interval from the provided date or date with time.

If the subtraction results in a value outside the bounds of the data type, the result is undefined.

Syntax

Alternative syntax:

Aliases: dateSub, DATE_SUB.

Arguments

  • unit — The type of interval to subtract. Note: This is not a String and must therefore not be quoted.

    Possible values:

    • second
    • minute
    • hour
    • day
    • week
    • month
    • quarter
    • year
  • value — Value of interval to subtract. Int.

  • date — The date or date with time from which value is subtracted. Date, Date32, DateTime or DateTime64.

Returned value

Date or date with time obtained by subtracting value, expressed in unit, from date. Date, Date32, DateTime or DateTime64.

Example

Result:

Result:

See Also

timestamp_add

Adds the specified time value with the provided date or date time value.

If the addition results in a value outside the bounds of the data type, the result is undefined.

Syntax

Aliases: timeStampAdd, TIMESTAMP_ADD.

Arguments

  • date — Date or date with time. Date, Date32, DateTime or DateTime64.

  • value — Value of interval to add. Int.

  • unit — The type of interval to add. String. Possible values:

    • second
    • minute
    • hour
    • day
    • week
    • month
    • quarter
    • year

Returned value

Date or date with time with the specified value expressed in unit added to date. Date, Date32, DateTime or DateTime64.

Example

Result:

timestamp_sub

Subtracts the time interval from the provided date or date with time.

If the subtraction results in a value outside the bounds of the data type, the result is undefined.

Syntax

Aliases: timeStampSub, TIMESTAMP_SUB.

Arguments

  • unit — The type of interval to subtract. String. Possible values:

    • second
    • minute
    • hour
    • day
    • week
    • month
    • quarter
    • year
  • value — Value of interval to subtract. Int.

  • date — Date or date with time. Date, Date32, DateTime or DateTime64.

Returned value

Date or date with time obtained by subtracting value, expressed in unit, from date. Date, Date32, DateTime or DateTime64.

Example

Result:

addDate

Adds the time interval to the provided date, date with time or String-encoded date / date with time.

If the addition results in a value outside the bounds of the data type, the result is undefined.

Syntax

Arguments

Returned value

Date or date with time obtained by adding interval to date. Date, Date32, DateTime or DateTime64.

Example

Result:

Alias: ADDDATE

See Also

subDate

Subtracts the time interval from the provided date, date with time or String-encoded date / date with time.

If the subtraction results in a value outside the bounds of the data type, the result is undefined.

Syntax

Arguments

Returned value

Date or date with time obtained by subtracting interval from date. Date, Date32, DateTime or DateTime64.

Example

Result:

Alias: SUBDATE

See Also

now

Returns the current date and time at the moment of query analysis. The function is a constant expression.

Alias: current_timestamp.

Syntax

Arguments

Returned value

Example

Query without timezone:

Result:

Query with the specified timezone:

Result:

now64

Returns the current date and time with sub-second precision at the moment of query analysis. The function is a constant expression.

Syntax

Arguments

  • scale - Tick size (precision): 10-precision seconds. Valid range: [ 0 : 9 ]. Typically, are used - 3 (default) (milliseconds), 6 (microseconds), 9 (nanoseconds).
  • timezoneTimezone name for the returned value (optional). String.

Returned value

  • Current date and time with sub-second precision. DateTime64.

Example

Result:

nowInBlock

Returns the current date and time at the moment of processing of each block of data. In contrast to the function now, it is not a constant expression, and the returned value will be different in different blocks for long-running queries.

It makes sense to use this function to generate the current time in long-running INSERT SELECT queries.

Syntax

Arguments

Returned value

  • Current date and time at the moment of processing of each block of data. DateTime.

Example

Result:

nowInBlock64

Returns the current date and time at the moment of processing of each block of data in milliseconds. In contrast to the function now64, it is not a constant expression, and the returned value will be different in different blocks for long-running queries.

It makes sense to use this function to generate the current time in long-running INSERT SELECT queries.

Syntax

Arguments

  • scale - Tick size (precision): 10-precision seconds. Valid range: [ 0 : 9 ]. Typical values used: 3 (milliseconds), 6 (microseconds), 9 (nanoseconds) (optional).

  • timezoneTimezone name for the returned value (optional). String.

Returned value

  • Current date and time at the moment of processing of each block of data with precision in 10-precision seconds. DateTime.

Example

Result:

Example with parameters

Result:

today

Returns the current date at moment of query analysis. It is the same as 'toDate(now())' and has aliases: curdate, current_date.

Syntax

Arguments

  • None

Returned value

Example

Query:

Result:

Running the query above on the 3rd of March 2024 would have returned the following response:

yesterday

Accepts zero arguments and returns yesterday's date at one of the moments of query analysis. The same as 'today() - 1'.

timeSlot

Round the time to the start of a half-an-hour length interval.

Syntax

Arguments

  • time — Time to round to the start of a half-an-hour length interval. DateTime/Date32/DateTime64.
  • time_zone — A String type const value or an expression representing the time zone. String.
Note

Though this function can take values of the extended types Date32 and DateTime64 as an argument, passing it a time outside the normal range (year 1970 to 2149 for Date / 2106 for DateTime) will produce wrong results.

Return type

  • Returns the time rounded to the start of a half-an-hour length interval. DateTime.

Example

Query:

Result:

toYYYYMM

Converts a date or date with time to a UInt32 number containing the year and month number (YYYY * 100 + MM). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.

This function is the opposite of function YYYYMMDDToDate().

Example

Result:

toYYYYMMDD

Converts a date or date with time to a UInt32 number containing the year and month number (YYYY * 10000 + MM * 100 + DD). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.

Example

Result:

toYYYYMMDDhhmmss

Converts a date or date with time to a UInt64 number containing the year and month number (YYYY * 10000000000 + MM * 100000000 + DD * 1000000 + hh * 10000 + mm * 100 + ss). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.

Example

Result:

YYYYMMDDToDate

Converts a number containing the year, month and day number to a Date.

This function is the opposite of function toYYYYMMDD().

The output is undefined if the input does not encode a valid Date value.

Syntax

Arguments

Returned value

  • a date created from the arguments. Date.

Example

Result:

YYYYMMDDToDate32

Like function YYYYMMDDToDate() but produces a Date32.

YYYYMMDDhhmmssToDateTime

Converts a number containing the year, month, day, hours, minute and second number to a DateTime.

The output is undefined if the input does not encode a valid DateTime value.

This function is the opposite of function toYYYYMMDDhhmmss().

Syntax

Arguments

  • yyyymmddhhmmss - A number representing the year, month and day. Integer, Float or Decimal.
  • timezone - Timezone for the returned value (optional).

Returned value

  • a date with time created from the arguments. DateTime.

Example

Result:

YYYYMMDDhhmmssToDateTime64

Like function YYYYMMDDhhmmssToDate() but produces a DateTime64.

Accepts an additional, optional precision parameter after the timezone parameter.

changeYear

Changes the year component of a date or date time.

Syntax

Arguments

Returned value

  • The same type as date_or_datetime.

Example

Result:

changeMonth

Changes the month component of a date or date time.

Syntax

Arguments

Returned value

  • Returns a value of same type as date_or_datetime.

Example

Result:

changeDay

Changes the day component of a date or date time.

Syntax

Arguments

Returned value

  • Returns a value of same type as date_or_datetime.

Example

Result:

changeHour

Changes the hour component of a date or date time.

Syntax

Arguments

Returned value

Example

Result:

changeMinute

Changes the minute component of a date or date time.

Syntax

Arguments

Returned value

Example

Result:

changeSecond

Changes the second component of a date or date time.

Syntax

Arguments

Returned value

Example

Result:

addYears

Adds a specified number of years to a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

addQuarters

Adds a specified number of quarters to a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

addMonths

Adds a specified number of months to a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

addWeeks

Adds a specified number of weeks to a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

addDays

Adds a specified number of days to a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

addHours

Adds a specified number of days to a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value o

Example

addMinutes

Adds a specified number of minutes to a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

addSeconds

Adds a specified number of seconds to a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

addMilliseconds

Adds a specified number of milliseconds to a date with time or a string-encoded date with time.

Syntax

Parameters

Returned value

  • Returns date_time plus num milliseconds. DateTime64.

Example

addMicroseconds

Adds a specified number of microseconds to a date with time or a string-encoded date with time.

Syntax

Parameters

Returned value

  • Returns date_time plus num microseconds. DateTime64.

Example

addNanoseconds

Adds a specified number of microseconds to a date with time or a string-encoded date with time.

Syntax

Parameters

Returned value

  • Returns date_time plus num nanoseconds. DateTime64.

Example

addInterval

Adds an interval to another interval or tuple of intervals.

Syntax

Parameters

Returned value

Note

Intervals of the same type will be combined into a single interval. For instance if toIntervalDay(1) and toIntervalDay(2) are passed then the result will be (3) rather than (1,1).

Example

Query:

Result:

addTupleOfIntervals

Consecutively adds a tuple of intervals to a Date or a DateTime.

Syntax

Parameters

Returned value

Example

Query:

Result:

subtractYears

Subtracts a specified number of years from a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

subtractQuarters

Subtracts a specified number of quarters from a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

subtractMonths

Subtracts a specified number of months from a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

subtractWeeks

Subtracts a specified number of weeks from a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

subtractDays

Subtracts a specified number of days from a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

subtractHours

Subtracts a specified number of hours from a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

subtractMinutes

Subtracts a specified number of minutes from a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

subtractSeconds

Subtracts a specified number of seconds from a date, a date with time or a string-encoded date / date with time.

Syntax

Parameters

Returned value

Example

subtractMilliseconds

Subtracts a specified number of milliseconds from a date with time or a string-encoded date with time.

Syntax

Parameters

Returned value

  • Returns date_time minus num milliseconds. DateTime64.

Example

subtractMicroseconds

Subtracts a specified number of microseconds from a date with time or a string-encoded date with time.

Syntax

Parameters

Returned value

  • Returns date_time minus num microseconds. DateTime64.

Example

subtractNanoseconds

Subtracts a specified number of nanoseconds from a date with time or a string-encoded date with time.

Syntax

Parameters

Returned value

  • Returns date_time minus num nanoseconds. DateTime64.

Example

subtractInterval

Adds a negated interval to another interval or tuple of intervals.

Syntax

Parameters

Returned value

Note

Intervals of the same type will be combined into a single interval. For instance if toIntervalDay(2) and toIntervalDay(1) are passed then the result will be (1) rather than (2,1)

Example

Query:

Result:

subtractTupleOfIntervals

Consecutively subtracts a tuple of intervals from a Date or a DateTime.

Syntax

Parameters

Returned value

Example

Query:

Result:

timeSlots

For a time interval starting at 'StartTime' and continuing for 'Duration' seconds, it returns an array of moments in time, consisting of points from this interval rounded down to the 'Size' in seconds. 'Size' is an optional parameter set to 1800 (30 minutes) by default. This is necessary, for example, when searching for pageviews in the corresponding session. Accepts DateTime and DateTime64 as 'StartTime' argument. For DateTime, 'Duration' and 'Size' arguments must be UInt32. For 'DateTime64' they must be Decimal64. Returns an array of DateTime/DateTime64 (return type matches the type of 'StartTime'). For DateTime64, the return value's scale can differ from the scale of 'StartTime' --- the highest scale among all given arguments is taken.

Syntax

Example

Result:

formatDateTime

Formats a Time according to the given Format string. Format is a constant expression, so you cannot have multiple formats for a single result column.

formatDateTime uses MySQL datetime format style, refer to https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_date-format.

The opposite operation of this function is parseDateTime.

Alias: DATE_FORMAT.

Syntax

Returned value(s)

Returns time and date values according to the determined format.

Replacement fields

Using replacement fields, you can define a pattern for the resulting string. "Example" column shows formatting result for 2018-01-02 22:33:44.

PlaceholderDescriptionExample
%aabbreviated weekday name (Mon-Sun)Mon
%babbreviated month name (Jan-Dec)Jan
%cmonth as an integer number (01-12), see 'Note 4' below01
%Cyear divided by 100 and truncated to integer (00-99)20
%dday of the month, zero-padded (01-31)02
%DShort MM/DD/YY date, equivalent to %m/%d/%y01/02/18
%eday of the month, space-padded ( 1-31), see 'Note 5' below  2
%ffractional second, see 'Note 1' and 'Note 2' below123456
%Fshort YYYY-MM-DD date, equivalent to %Y-%m-%d2018-01-02
%gtwo-digit year format, aligned to ISO 8601, abbreviated from four-digit notation18
%Gfour-digit year format for ISO week number, calculated from the week-based year defined by the ISO 8601 standard, normally useful only with %V2018
%hhour in 12h format (01-12)09
%Hhour in 24h format (00-23)22
%iminute (00-59)33
%Ihour in 12h format (01-12)10
%jday of the year (001-366)002
%khour in 24h format (00-23), see 'Note 4' below14
%lhour in 12h format (01-12), see 'Note 4' below09
%mmonth as an integer number (01-12)01
%Mfull month name (January-December), see 'Note 3' belowJanuary
%nnew-line character ('')
%pAM or PM designationPM
%QQuarter (1-4)1
%r12-hour HH:MM AM/PM time, equivalent to %h:%i %p10:30 PM
%R24-hour HH:MM time, equivalent to %H:%i22:33
%ssecond (00-59)44
%Ssecond (00-59)44
%thorizontal-tab character (')
%TISO 8601 time format (HH:MM:SS), equivalent to %H:%i:%S22:33:44
%uISO 8601 weekday as number with Monday as 1 (1-7)2
%VISO 8601 week number (01-53)01
%wweekday as a integer number with Sunday as 0 (0-6)2
%Wfull weekday name (Monday-Sunday)Monday
%yYear, last two digits (00-99)18
%YYear2018
%zTime offset from UTC as +HHMM or -HHMM-0500
%%a % sign%

Note 1: In ClickHouse versions earlier than v23.4, %f prints a single zero (0) if the formatted value is a Date, Date32 or DateTime (which have no fractional seconds) or a DateTime64 with a precision of 0. The previous behavior can be restored using setting formatdatetime_f_prints_single_zero = 1.

Note 2: In ClickHouse versions earlier than v25.1, %f prints as many digits as specified by the scale of the DateTime64 instead of fixed 6 digits. The previous behavior can be restored using setting formatdatetime_f_prints_scale_number_of_digits= 1.

Note 3: In ClickHouse versions earlier than v23.4, %M prints the minute (00-59) instead of the full month name (January-December). The previous behavior can be restored using setting formatdatetime_parsedatetime_m_is_month_name = 0.

Note 4: In ClickHouse versions earlier than v23.11, function parseDateTime required leading zeros for formatters %c (month) and %l/%k (hour), e.g. 07. In later versions, the leading zero may be omitted, e.g. 7. The previous behavior can be restored using setting parsedatetime_parse_without_leading_zeros = 0. Note that function formatDateTime by default still prints leading zeros for %c and %l/%k to not break existing use cases. This behavior can be changed by setting formatdatetime_format_without_leading_zeros = 1.

Note 5: In ClickHouse versions earlier than v25.5, function parseDateTime required for formatter %e that single-digit days are space padded, e.g. 3. In later versions, space padding is optional, e.g. 3 and 3 work. To retain the previous behaviour, set setting parsedatetime_e_requires_space_padding = 1. Similarly, formatter %e in function formatDateTime previously space-padded single-printed unconditionally whereas it now prints them without leading whitespace. To retain the previous behavior, set setting formatdatetime_e_with_space_padding = 1.

Example

Result:

Result:

Additionally, the formatDateTime function can take a third String argument containing the name of the time zone. Example: Asia/Istanbul. In this case, the time is formatted according to the specified time zone.

Example

See Also

formatDateTimeInJodaSyntax

Similar to formatDateTime, except that it formats datetime in Joda style instead of MySQL style. Refer to https://joda-time.sourceforge.net/apidocs/org/joda/time/format/DateTimeFormat.html.

The opposite operation of this function is parseDateTimeInJodaSyntax.

Replacement fields

Using replacement fields, you can define a pattern for the resulting string.

PlaceholderDescriptionPresentationExamples
GeratextAD
Ccentury of era (>=0)number20
Yyear of era (>=0)year1996
xweekyear (not supported yet)year1996
wweek of weekyear (not supported yet)number27
eday of weeknumber2
Eday of weektextTuesday; Tue
yyearyear1996
Dday of yearnumber189
Mmonth of yearmonthJuly; Jul; 07
dday of monthnumber10
ahalfday of daytextPM
Khour of halfday (0~11)number0
hclockhour of halfday (1~12)number12
Hhour of day (0~23)number0
kclockhour of day (1~24)number24
mminute of hournumber30
ssecond of minutenumber55
Sfraction of secondnumber978
ztime zonetextEastern Standard Time; EST
Ztime zone offsetzone-0800; -0812
'escape for textdelimiter
''single quoteliteral'

Example

Result:

dateName

Returns specified part of date.

Syntax

Arguments

  • date_part — Date part. Possible values: 'year', 'quarter', 'month', 'week', 'dayofyear', 'day', 'weekday', 'hour', 'minute', 'second'. String.
  • date — Date. Date, Date32, DateTime or DateTime64.
  • timezone — Timezone. Optional. String.

Returned value

  • The specified part of date. String

Example

Result:

monthName

Returns name of the month.

Syntax

Arguments

Returned value

  • The name of the month. String

Example

Result:

fromUnixTimestamp

This function converts a Unix timestamp to a calendar date and a time of a day.

It can be called in two ways:

When given a single argument of type Integer, it returns a value of type DateTime, i.e. behaves like toDateTime.

Alias: FROM_UNIXTIME.

Example:

Result:

When given two or three arguments where the first argument is a value of type Integer, Date, Date32, DateTime or DateTime64, the second argument is a constant format string and the third argument is an optional constant time zone string, the function returns a value of type String, i.e. it behaves like formatDateTime. In this case, MySQL's datetime format style is used.

Example:

Result:

See Also

fromUnixTimestampInJodaSyntax

Same as fromUnixTimestamp but when called in the second way (two or three arguments), the formatting is performed using Joda style instead of MySQL style.

Example:

Result:

toModifiedJulianDay

Converts a Proleptic Gregorian calendar date in text form YYYY-MM-DD to a Modified Julian Day number in Int32. This function supports date from 0000-01-01 to 9999-12-31. It raises an exception if the argument cannot be parsed as a date, or the date is invalid.

Syntax

Arguments

Returned value

  • Modified Julian Day number. Int32.

Example

Result:

toModifiedJulianDayOrNull

Similar to toModifiedJulianDay(), but instead of raising exceptions it returns NULL.

Syntax

Arguments

Returned value

Example

Result:

fromModifiedJulianDay

Converts a Modified Julian Day number to a Proleptic Gregorian calendar date in text form YYYY-MM-DD. This function supports day number from -678941 to 2973483 (which represent 0000-01-01 and 9999-12-31 respectively). It raises an exception if the day number is outside of the supported range.

Syntax

Arguments

Returned value

Example

Result:

fromModifiedJulianDayOrNull

Similar to fromModifiedJulianDayOrNull(), but instead of raising exceptions it returns NULL.

Syntax

Arguments

Returned value

Example

Result:

toUTCTimestamp

Convert DateTime/DateTime64 type value from other time zone to UTC timezone timestamp. This function is mainly included for compatibility with Apache Spark and similar frameworks.

Syntax

Arguments

  • time_val — A DateTime/DateTime64 type const value or an expression . DateTime/DateTime64 types
  • time_zone — A String type const value or an expression represent the time zone. String types

Returned value

  • DateTime/DateTime64 in text form

Example

Result:

fromUTCTimestamp

Convert DateTime/DateTime64 type value from UTC timezone to other time zone timestamp. This function is mainly included for compatibility with Apache Spark and similar frameworks.

Syntax

Arguments

  • time_val — A DateTime/DateTime64 type const value or an expression . DateTime/DateTime64 types
  • time_zone — A String type const value or an expression represent the time zone. String types

Returned value

  • DateTime/DateTime64 in text form

Example

Result:

UTCTimestamp

Returns the current date and time at the moment of query analysis. The function is a constant expression.

Note

This function gives the same result that now('UTC') would. It was added only for MySQL support and now is the preferred usage.

Syntax

Alias: UTC_timestamp.

Returned value

  • Returns the current date and time at the moment of query analysis. DateTime.

Example

Query:

Result:

timeDiff

Returns the difference between two dates or dates with time values. The difference is calculated in units of seconds. It is same as dateDiff and was added only for MySQL support. dateDiff is preferred.

Syntax

Arguments*

Returned value

The difference between two dates or dates with time values in seconds.

Example

Query:

Result:

UTCTimestamp

Introduced in: v22.11

Returns the current date and time at the moment of query analysis. The function is a constant expression.

This function gives the same result that now('UTC') would. It was added only for MySQL support. now is the preferred usage.

Syntax

Arguments

  • None. Returned value

Returns the current date and time at the moment of query analysis. DateTime

Examples

Get current UTC timestamp

YYYYMMDDToDate

Introduced in: v23.9

Converts a number containing the year, month and day number to a Date. This function is the opposite of function toYYYYMMDD(). The output is undefined if the input does not encode a valid Date value.

Syntax

Arguments

Returned value

Returns a Date value from the provided arguments Date

Examples

Example

YYYYMMDDToDate32

Introduced in: v23.9

Converts a number containing the year, month and day number to a Date32. This function is the opposite of function toYYYYMMDD(). The output is undefined if the input does not encode a valid Date32 value.

Syntax

Arguments

Returned value

Returns a Date32 value from the provided arguments Date32

Examples

Example

YYYYMMDDhhmmssToDateTime

Introduced in: v23.9

Converts a number containing the year, month, day, hour, minute, and second to a DateTime. This function is the opposite of function toYYYYMMDDhhmmss(). The output is undefined if the input does not encode a valid DateTime value.

Syntax

Arguments

  • YYYYMMDDhhmmss — Number containing the year, month, day, hour, minute, and second. (U)Int* or Float* or Decimal
  • timezone — Timezone name. String

Returned value

Returns a DateTime value from the provided arguments DateTime

Examples

Example

YYYYMMDDhhmmssToDateTime64

Introduced in: v23.9

Converts a number containing the year, month, day, hour, minute, and second to a DateTime64. This function is the opposite of function toYYYYMMDDhhmmss(). The output is undefined if the input does not encode a valid DateTime64 value.

Syntax

Arguments

  • YYYYMMDDhhmmss — Number containing the year, month, day, hour, minute, and second. (U)Int* or Float* or Decimal
  • precision — Precision for the fractional part (0-9). UInt8
  • timezone — Timezone name. String

Returned value

Returns a DateTime64 value from the provided arguments DateTime64

Examples

Example

addDate

Introduced in: v23.9

Adds the time interval to the provided date, date with time or string-encoded date or date with time. If the addition results in a value outside the bounds of the data type, the result is undefined.

Syntax

Arguments

Returned value

Returns date or date with time obtained by adding interval to datetime. Date or Date32 or DateTime or DateTime64

Examples

Add interval to date

addDays

Introduced in: v1.1

Adds a specified number of days to a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime plus num days. Date or Date32 or DateTime or DateTime64

Examples

Add days to different date types

Using alternative INTERVAL syntax

addHours

Introduced in: v1.1

Adds a specified number of hours to a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime plus num hours DateTime or DateTime64(3)

Examples

Add hours to different date types

Using alternative INTERVAL syntax

addInterval

Introduced in: v22.11

Adds an interval to another interval or tuple of intervals.

Note: Intervals of the same type will be combined into a single interval. For instance if toIntervalDay(1) and toIntervalDay(2) are passed then the result will be (3) rather than (1,1).

Syntax

Arguments

Returned value

Returns a tuple of intervals Tuple(Interval)

Examples

Add intervals

addMicroseconds

Introduced in: v22.6

Adds a specified number of microseconds to a date with time or a string-encoded date with time.

Syntax

Arguments

Returned value

Returns date_time plus num microseconds DateTime64

Examples

Add microseconds to different date time types

Using alternative INTERVAL syntax

addMilliseconds

Introduced in: v22.6

Adds a specified number of milliseconds to a date with time or a string-encoded date with time.

Syntax

Arguments

Returned value

Returns datetime plus num milliseconds DateTime64

Examples

Add milliseconds to different date time types

Using alternative INTERVAL syntax

addMinutes

Introduced in: v1.1

Adds a specified number of minutes to a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime plus num minutes DateTime or DateTime64(3)

Examples

Add minutes to different date types

Using alternative INTERVAL syntax

addMonths

Introduced in: v1.1

Adds a specified number of months to a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime plus num months Date or Date32 or DateTime or DateTime64

Examples

Add months to different date types

Using alternative INTERVAL syntax

addNanoseconds

Introduced in: v22.6

Adds a specified number of nanoseconds to a date with time or a string-encoded date with time.

Syntax

Arguments

Returned value

Returns datetime plus num nanoseconds DateTime64

Examples

Add nanoseconds to different date time types

Using alternative INTERVAL syntax

addQuarters

Introduced in: v20.1

Adds a specified number of quarters to a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime plus num quarters Date or Date32 or DateTime or DateTime64

Examples

Add quarters to different date types

Using alternative INTERVAL syntax

addSeconds

Introduced in: v1.1

Adds a specified number of seconds to a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime plus num seconds DateTime or DateTime64(3)

Examples

Add seconds to different date types

Using alternative INTERVAL syntax

addTupleOfIntervals

Introduced in: v22.11

Consecutively adds a tuple of intervals to a date or a date with time.

Syntax

Arguments

Returned value

Returns date with added intervals Date or Date32 or DateTime or DateTime64

Examples

Add tuple of intervals to date

addWeeks

Introduced in: v1.1

Adds a specified number of weeks to a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime plus num weeks Date or Date32 or DateTime or DateTime64

Examples

Add weeks to different date types

Using alternative INTERVAL syntax

addYears

Introduced in: v1.1

Adds a specified number of years to a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime plus num years Date or Date32 or DateTime or DateTime64

Examples

Add years to different date types

Using alternative INTERVAL syntax

age

Introduced in: v23.1

Returns the unit component of the difference between startdate and enddate. The difference is calculated using a precision of 1 nanosecond.

For example, the difference between 2021-12-29 and 2022-01-01 is 3 days for the day unit, 0 months for the month unit, and 0 years for the year unit.

For an alternative to age, see function date_diff.

Syntax

Arguments

  • unit — The type of interval for result.
UnitPossible values
nanosecondnanosecond, nanoseconds, ns
microsecondmicrosecond, microseconds, us, u
millisecondmillisecond, milliseconds, ms
secondsecond, seconds, ss, s
minuteminute, minutes, mi, n
hourhour, hours, hh, h
dayday, days, dd, d
weekweek, weeks, wk, ww
monthmonth, months, mm, m
quarterquarter, quarters, qq, q
yearyear, years, yyyy, yy
  • startdate — The first time value to subtract (the subtrahend). Date or Date32 or DateTime or DateTime64
  • enddate — The second time value to subtract from (the minuend). Date or Date32 or DateTime or DateTime64
  • timezone — Optional. Timezone name. If specified, it is applied to both startdate and enddate. If not specified, timezones of startdate and enddate are used. If they are not the same, the result is unspecified. String

Returned value

Returns the difference between enddate and startdate expressed in unit. Int32

Examples

Calculate age in hours

Calculate age in different units

changeDay

Introduced in: v24.7

Changes the day component of a date or date time.

Syntax

Arguments

Returned value

Returns a value of the same type as date_or_datetime with modified day component. Date or Date32 or DateTime or DateTime64

Examples

Usage example

changeHour

Introduced in: v24.7

Changes the hour component of a date or date time.

Syntax

Arguments

Returned value

Returns a value of the same type as date_or_datetime with modified hour component. DateTime or DateTime64

Examples

Usage example

changeMinute

Introduced in: v24.7

Changes the minute component of a date or date time.

Syntax

Arguments

Returned value

Returns a value of the same type as date_or_datetime with modified minute component. DateTime or DateTime64

Examples

Usage example

changeMonth

Introduced in: v24.7

Changes the month component of a date or date time.

Syntax

Arguments

Returned value

Returns a value of the same type as date_or_datetime with modified month component. Date or Date32 or DateTime or DateTime64

Examples

Usage example

changeSecond

Introduced in: v24.7

Changes the second component of a date or date time.

Syntax

Arguments

Returned value

Returns a value of the same type as date_or_datetime with modified seconds component. DateTime or DateTime64

Examples

Usage example

changeYear

Introduced in: v24.7

Changes the year component of a date or date time.

Syntax

Arguments

Returned value

Returns a value of the same type as date_or_datetime with modified year component. Date or Date32 or DateTime or DateTime64

Examples

Usage example

dateName

Introduced in: v21.7

Returns the specified part of the date.

Possible values:

  • 'year'
  • 'quarter'
  • 'month'
  • 'week'
  • 'dayofyear'
  • 'day'
  • 'weekday'
  • 'hour'
  • 'minute'
  • 'second'

Syntax

Arguments

Returned value

Returns the specified part of date. String

Examples

Extract different date parts

dateTrunc

Introduced in: v20.8

Truncates a date and time value to the specified part of the date.

Syntax

Arguments

  • unit — The type of interval to truncate the result. unit argument is case-insensitive. | Unit | Compatibility | |--------------|---------------------------------| | nanosecond | Compatible only with DateTime64 | | microsecond| Compatible only with DateTime64 | | millisecond| Compatible only with DateTime64 | | second | | | minute | | | hour | | | day | | | week | | | month | | | quarter | | | year | | String
  • datetime — Date and time. Date or Date32 or DateTime or DateTime64
  • timezone — Optional. Timezone name for the returned datetime. If not specified, the function uses the timezone of the datetime parameter. String

Returned value

Returns the truncated date and time value.

Unit Argumentdatetime ArgumentReturn Type
Year, Quarter, Month, WeekDate32 or DateTime64 or Date or DateTimeDate32 or Date
Day, Hour, Minute, SecondDate32, DateTime64, Date, or DateTimeDateTime64 or DateTime
Millisecond, Microsecond,AnyDateTime64
Nanosecondwith scale 3, 6, or 9

Examples

Truncate without timezone

Truncate with specified timezone

formatDateTime

Introduced in: v1.1

Formats a date or date with time according to the given format string. format is a constant expression, so you cannot have multiple formats for a single result column.

formatDateTime uses MySQL datetime format style, refer to the mysql docs.

The opposite operation of this function is parseDateTime.

Using replacement fields, you can define a pattern for the resulting string. The example column in the table below shows formatting result for 2018-01-02 22:33:44.

Replacement fields:

PlaceholderDescriptionExample
%aabbreviated weekday name (Mon-Sun)Mon
%babbreviated month name (Jan-Dec)Jan
%cmonth as an integer number (01-12)01
%Cyear divided by 100 and truncated to integer (00-99)20
%dday of the month, zero-padded (01-31)02
%DShort MM/DD/YY date, equivalent to %m/%d/%y01/02/18
%eday of the month, space-padded (1-31)2
%ffractional second123456
%Fshort YYYY-MM-DD date, equivalent to %Y-%m-%d2018-01-02
%gtwo-digit year format, aligned to ISO 860118
%Gfour-digit year format for ISO week number2018
%hhour in 12h format (01-12)09
%Hhour in 24h format (00-23)22
%iminute (00-59)33
%Ihour in 12h format (01-12)10
%jday of the year (001-366)002
%khour in 24h format (00-23)14
%lhour in 12h format (01-12)09
%mmonth as an integer number (01-12)01
%Mfull month name (January-December)January
%nnew-line character
%pAM or PM designationPM
%QQuarter (1-4)1
%r12-hour HH:MM AM/PM time, equivalent to %h:%i %p10:30 PM
%R24-hour HH:MM time, equivalent to %H:%i22:33
%ssecond (00-59)44
%Ssecond (00-59)44
%thorizontal-tab character
%TISO 8601 time format (HH:MM:SS), equivalent to %H:%i:%S22:33:44
%uISO 8601 weekday as number with Monday as 1 (1-7)2
%VISO 8601 week number (01-53)01
%wweekday as a integer number with Sunday as 0 (0-6)2
%Wfull weekday name (Monday-Sunday)Monday
%yYear, last two digits (00-99)18
%YYear2018
%zTime offset from UTC as +HHMM or -HHMM-0500
%%a % sign%
  • In ClickHouse versions earlier than v23.4, %f prints a single zero (0) if the formatted value is a Date, Date32 or DateTime (which have no fractional seconds) or a DateTime64 with a precision of 0.
  • In ClickHouse versions earlier than v25.1, %f prints as many digits as specified by the scale of the DateTime64 instead of fixed 6 digits.
  • In ClickHouse versions earlier than v23.4, %M prints the minute (00-59) instead of the full month name (January-December).

Syntax

Arguments

  • datetime — A date or date time to format. Date or Date32 or DateTime or DateTime64
  • format — Format string with replacement fields. String
  • timezone — Optional. Timezone name for the formatted time. String

Returned value

Returns time and date values according to the determined format. String

Examples

Format date with year placeholder

Format DateTime64 with fractional seconds

Format with timezone

formatDateTimeInJodaSyntax

Introduced in: v20.1

Similar to formatDateTime, except that it formats datetime in Joda style instead of MySQL style. Refer to Joda Time documentation.

The opposite operation of this function is parseDateTimeInJodaSyntax.

Using replacement fields, you can define a pattern for the resulting string.

Replacement fields:

PlaceholderDescriptionPresentationExamples
GeratextAD
Ccentury of era (>=0)number20
Yyear of era (>=0)year1996
xweekyear (not supported yet)year1996
wweek of weekyear (not supported yet)number27
eday of weeknumber2
Eday of weektextTuesday; Tue
yyearyear1996
Dday of yearnumber189
Mmonth of yearmonthJuly; Jul; 07
dday of monthnumber10
ahalfday of daytextPM
Khour of halfday (0~11)number0
hclockhour of halfday (1~12)number12
Hhour of day (0~23)number0
kclockhour of day (1~24)number24
mminute of hournumber30
ssecond of minutenumber55
Sfraction of secondnumber978
ztime zonetextEastern Standard Time; EST
Ztime zone offsetzone-0800; -0812
'escape for textdelimiter
''single quoteliteral'

Syntax

Arguments

  • datetime — A date or date time to format. DateTime or Date or Date32 or DateTime64
  • format — Format string with Joda-style replacement fields. String
  • timezone — Optional. Timezone name for the formatted time. String

Returned value

Returns time and date values according to the determined format. String

Examples

Format datetime using Joda syntax

fromDaysSinceYearZero

Introduced in: v23.11

For a given number of days elapsed since 1 January 0000, returns the corresponding date in the proleptic Gregorian calendar defined by ISO 8601.

The calculation is the same as in MySQL's FROM_DAYS() function. The result is undefined if it cannot be represented within the bounds of the Date type.

Syntax

Arguments

  • days — The number of days passed since year zero. UInt32

Returned value

Returns the date corresponding to the number of days passed since year zero. Date

Examples

Convert days since year zero to dates

fromDaysSinceYearZero32

Introduced in: v23.11

For a given number of days elapsed since 1 January 0000, returns the corresponding date in the proleptic Gregorian calendar defined by ISO 8601. The calculation is the same as in MySQL's FROM_DAYS() function. The result is undefined if it cannot be represented within the bounds of the Date32 type.

Syntax

Arguments

  • days — The number of days passed since year zero. UInt32

Returned value

Returns the date corresponding to the number of days passed since year zero. Date32

Examples

Convert days since year zero to dates

fromModifiedJulianDay

Introduced in: v21.1

Converts a Modified Julian Day number to a Proleptic Gregorian calendar date in text form YYYY-MM-DD. This function supports day number from -678941 to 2973483 (which represent 0000-01-01 and 9999-12-31 respectively). It raises an exception if the day number is outside of the supported range.

Syntax

Arguments

  • day — Modified Julian Day number. (U)Int*

Returned value

Returns date in text form. String

Examples

Convert Modified Julian Day to date

fromModifiedJulianDayOrNull

Introduced in: v21.1

Similar to fromModifiedJulianDay(), but instead of raising exceptions it returns NULL.

Syntax

Arguments

  • day — Modified Julian Day number. (U)Int*

Returned value

Returns date in text form for valid day argument, otherwise null. Nullable(String)

Examples

Convert Modified Julian Day to date with null handling

fromUTCTimestamp

Introduced in: v22.1

Converts a date or date with time value from UTC timezone to a date or date with time value with the specified time zone. This function is mainly included for compatibility with Apache Spark and similar frameworks.

Syntax

Arguments

  • datetime — A date or date with time const value or an expression. DateTime or DateTime64
  • time_zone — A String type const value or an expression representing the time zone. String

Returned value

Returns DateTime/DateTime64 in the specified timezone. DateTime or DateTime64

Examples

Convert UTC timezone to specified timezone

fromUnixTimestamp

Introduced in: v20.8

This function converts a Unix timestamp to a calendar date and a time of a day.

It can be called in two ways:

Syntax

Arguments

  • timestamp — Unix timestamp or date/date with time value. (U)Int* or Date or Date32 or DateTime or DateTime64
  • format — Optional. Constant format string for output formatting. String
  • timezone — Optional. Constant time zone string. String

Returned value

Returns DateTime of the timestamp when called with one argument, or a String when called with two or three arguments. DateTime or String

Examples

Convert Unix timestamp to DateTime

Convert Unix timestamp with format

fromUnixTimestampInJodaSyntax

Introduced in: v23.1

This function converts a Unix timestamp to a calendar date and a time of a day.

It can be called in two ways:

When given a single argument of type Integer, it returns a value of type DateTime, i.e. behaves like toDateTime.

When given two or three arguments where the first argument is a value of type Integer, Date, Date32, DateTime or DateTime64, the second argument is a constant format string and the third argument is an optional constant time zone string, the function returns a value of type String, i.e. it behaves like formatDateTimeInJodaSyntax. In this case, Joda datetime format style is used.

Syntax

Arguments

  • timestamp — Unix timestamp or date/time value. (U)Int* or Date or Date32 or DateTime or DateTime64
  • format — Optional. Constant format string using Joda syntax for output formatting. String
  • timezone — Optional. Constant time zone string. String

Returned value

Returns a date with time when called with one argument, or a String when called with two or three arguments.} DateTime or String

Examples

Convert Unix timestamp with Joda format

makeDate

Introduced in: v22.6

Creates a Date from either:

  • a year, month and day
  • a year and day of year

Syntax

Arguments

Returned value

Returns a Date value constructed from the provided arguments Date

Examples

Date from a year, month, day

Date from year and day of year

makeDate32

Introduced in: v22.6

Creates a Date32 from either:

  • a year, month and day
  • a year and day of year

Syntax

Arguments

Returned value

Returns a Date32 value constructed from the provided arguments Date32

Examples

Date32 from a year, month, day

Date32 from year and day of year

makeDateTime

Introduced in: v22.6

Creates a DateTime from year, month, day, hour, minute, and second, with optional timezone.

Syntax

Arguments

Returned value

Returns a DateTime value constructed from the provided arguments DateTime

Examples

DateTime from year, month, day, hour, minute, second

makeDateTime64

Introduced in: v22.6

Creates a DateTime64 from year, month, day, hour, minute, second, with optional fraction, precision, and timezone.

Syntax

Arguments

Returned value

Returns a DateTime64 value constructed from the provided arguments DateTime64

Examples

DateTime64 from year, month, day, hour, minute, second

monthName

Introduced in: v22.1

Returns the name of the month as a string from a date or date with time value.

Syntax

Arguments

Returned value

Returns the name of the month. String

Examples

Get month name from date

now

Introduced in: v1.1

Returns the current date and time at the moment of query analysis. The function is a constant expression.

Syntax

Arguments

  • timezone — Optional. Timezone name for the returned value. String

Returned value

Returns the current date and time. DateTime

Examples

Query without timezone

Query with specified timezone

now64

Introduced in: v20.1

Returns the current date and time with sub-second precision at the moment of query analysis. The function is a constant expression.

Syntax

Arguments

  • scale — Optional. Tick size (precision): 10^-precision seconds. Valid range: [0 : 9]. Typically, are used - 3 (default) (milliseconds), 6 (microseconds), 9 (nanoseconds). UInt8
  • timezone — Optional. Timezone name for the returned value. String

Returned value

Returns current date and time with sub-second precision. DateTime64

Examples

Query with default and custom precision

nowInBlock

Introduced in: v22.8

Returns the current date and time at the moment of processing of each block of data. In contrast to the function now, it is not a constant expression, and the returned value will be different in different blocks for long-running queries.

It makes sense to use this function to generate the current time in long-running INSERT SELECT queries.

Syntax

Arguments

  • timezone — Optional. Timezone name for the returned value. String

Returned value

Returns the current date and time at the moment of processing of each block of data. DateTime

Examples

Difference with the now() function

nowInBlock64

Introduced in: v25.8

Returns the current date and time at the moment of processing of each block of data in milliseconds. In contrast to the function now64, it is not a constant expression, and the returned value will be different in different blocks for long-running queries.

It makes sense to use this function to generate the current time in long-running INSERT SELECT queries.

Syntax

Arguments

  • scale — Optional. Tick size (precision): 10^-precision seconds. Valid range: [0 : 9]. Typically, are used - 3 (default) (milliseconds), 6 (microseconds), 9 (nanoseconds). UInt8
  • timezone — Optional. Timezone name for the returned value. String

Returned value

Returns the current date and time at the moment of processing of each block of data with sub-second precision. DateTime64

Examples

Difference with the now64() function

serverTimezone

Introduced in: v23.6

Returns the timezone of the server, i.e. the value of the timezone setting. If the function is executed in the context of a distributed table, then it generates a normal column with values relevant to each shard. Otherwise, it produces a constant value.

Syntax

Arguments

  • None. Returned value

Returns the server timezone as a String

Examples

Get server time zone

subDate

Introduced in: v23.9

Subtracts the time interval from the provided date, date with time or string-encoded date or date with time. If the subtraction results in a value outside the bounds of the data type, the result is undefined.

Syntax

Arguments

Returned value

Returns date or date with time obtained by subtracting interval from datetime. Date or Date32 or DateTime or DateTime64

Examples

Subtract interval from date

subtractDays

Introduced in: v1.1

Subtracts a specified number of days from a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime minus num days Date or Date32 or DateTime or DateTime64

Examples

Subtract days from different date types

Using alternative INTERVAL syntax

subtractHours

Introduced in: v1.1

Subtracts a specified number of hours from a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime minus num hours DateTime or DateTime64(3)

Examples

Subtract hours from different date types

Using alternative INTERVAL syntax

subtractInterval

Introduced in: v22.11

Adds a negated interval to another interval or tuple of intervals.

Note: Intervals of the same type will be combined into a single interval. For instance if toIntervalDay(2) and toIntervalDay(1) are passed then the result will be (1) rather than (2,1).

Syntax

Arguments

Returned value

Returns a tuple of intervals Tuple(T)

Examples

Subtract intervals

subtractMicroseconds

Introduced in: v22.6

Subtracts a specified number of microseconds from a date with time or a string-encoded date with time.

Syntax

Arguments

Returned value

Returns datetime minus num microseconds DateTime64

Examples

Subtract microseconds from different date time types

Using alternative INTERVAL syntax

subtractMilliseconds

Introduced in: v22.6

Subtracts a specified number of milliseconds from a date with time or a string-encoded date with time.

Syntax

Arguments

Returned value

Returns datetime minus num milliseconds DateTime64

Examples

Subtract milliseconds from different date time types

Using alternative INTERVAL syntax

subtractMinutes

Introduced in: v1.1

Subtracts a specified number of minutes from a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime minus num minutes DateTime or DateTime64(3)

Examples

Subtract minutes from different date types

Using alternative INTERVAL syntax

subtractMonths

Introduced in: v1.1

Subtracts a specified number of months from a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime minus num months Date or Date32 or DateTime or DateTime64

Examples

Subtract months from different date types

Using alternative INTERVAL syntax

subtractNanoseconds

Introduced in: v20.1

Subtracts a specified number of nanoseconds from a date with time or a string-encoded date with time.

Syntax

Arguments

Returned value

Returns datetime minus num nanoseconds DateTime64

Examples

Subtract nanoseconds from different date time types

Using alternative INTERVAL syntax

subtractQuarters

Introduced in: v20.1

Subtracts a specified number of quarters from a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime minus num quarters Date or Date32 or DateTime or DateTime64

Examples

Subtract quarters from different date types

Using alternative INTERVAL syntax

subtractSeconds

Introduced in: v1.1

Subtracts a specified number of seconds from a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime minus num seconds DateTime or DateTime64(3)

Examples

Subtract seconds from different date types

Using alternative INTERVAL syntax

subtractTupleOfIntervals

Introduced in: v22.11

Consecutively subtracts a tuple of intervals from a date or a date with time.

Syntax

Arguments

Returned value

Returns date with subtracted intervals Date or Date32 or DateTime or DateTime64

Examples

Subtract tuple of intervals from date

subtractWeeks

Introduced in: v1.1

Subtracts a specified number of weeks from a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime minus num weeks Date or Date32 or DateTime or DateTime64

Examples

Subtract weeks from different date types

Using alternative INTERVAL syntax

subtractYears

Introduced in: v1.1

Subtracts a specified number of years from a date, a date with time or a string-encoded date or date with time.

Syntax

Arguments

Returned value

Returns datetime minus num years Date or Date32 or DateTime or DateTime64

Examples

Subtract years from different date types

Using alternative INTERVAL syntax

timeDiff

Introduced in: v23.4

Returns the count of the specified unit boundaries crossed between the startdate and the enddate. The difference is calculated using relative units. For example, the difference between 2021-12-29 and 2022-01-01 is 3 days for unit day (see toRelativeDayNum), 1 month for unit month (see toRelativeMonthNum) and 1 year for unit year (see toRelativeYearNum).

If the unit week was specified, then date_diff assumes that weeks start on Monday. Note that this behavior is different from that of function toWeek() in which weeks start by default on Sunday.

For an alternative to date_diff, see function age.

Syntax

Arguments

  • unit — The type of interval for result.
UnitPossible values
nanosecondnanosecond, nanoseconds, ns
microsecondmicrosecond, microseconds, us, u
millisecondmillisecond, milliseconds, ms
secondsecond, seconds, ss, s
minuteminute, minutes, mi, n
hourhour, hours, hh, h
dayday, days, dd, d
weekweek, weeks, wk, ww
monthmonth, months, mm, m
quarterquarter, quarters, qq, q
yearyear, years, yyyy, yy
  • startdate — The first time value to subtract (the subtrahend). Date or Date32 or DateTime or DateTime64
  • enddate — The second time value to subtract from (the minuend). Date or Date32 or DateTime or DateTime64
  • timezone — Optional. Timezone name. If specified, it is applied to both startdate and enddate. If not specified, timezones of startdate and enddate are used. If they are not the same, the result is unspecified. String

Returned value

Returns the difference between enddate and startdate expressed in unit. Int64

Examples

Calculate date difference in hours

Calculate date difference in different units

timeSlot

Introduced in: v1.1

Round the time to the start of a half-an-hour length interval.

Note

Although this function can take values of the extended types Date32 and DateTime64 as an argument, passing it a time outside the normal range (year 1970 to 2149 for Date / 2106 for DateTime) will produce wrong results.

Syntax

Arguments

  • time — Time to round to the start of a half-an-hour length interval. DateTime or Date32 or DateTime64
  • time_zone — Optional. A String type const value or an expression representing the time zone. String

Returned value

Returns the time rounded to the start of a half-an-hour length interval. DateTime

Examples

Round time to half-hour interval

timeSlots

Introduced in: v1.1

For a time interval starting at StartTime and continuing for Duration seconds, it returns an array of moments in time, consisting of points from this interval rounded down to the Size in seconds. Size is an optional parameter set to 1800 (30 minutes) by default.

This is necessary, for example, when searching for pageviews in the corresponding session.

For DateTime64, the return value's scale can differ from the scale of StartTime. The highest scale among all given arguments is taken.

Syntax

Arguments

Returned value

Returns an array of DateTime/DateTime64 (return type matches the type of StartTime). For DateTime64, the return value's scale can differ from the scale of StartTime - the highest scale among all given arguments is taken. Array(DateTime) or Array(DateTime64)

Examples

Generate time slots for an interval

timestamp

Introduced in: v23.9

Converts the first argument expr to type DateTime64(6). If a second argument expr_time is provided, it adds the specified time to the converted value.

Syntax

Arguments

  • expr — Date or date with time. String
  • expr_time — Optional. Time to add to the converted value. String

Returned value

Returns the converted value of expr, or expr with added time DateTime64(6)

Examples

Convert date string to DateTime64(6)

Add time to date string

timezone

Introduced in: v1.1

Returns the time zone name of the current session or converts a time zone offset or name to a canonical time zone name.

Syntax

Arguments

  • None. Returned value

Returns the canonical time zone name as a String

Examples

Get current session time zone

timezoneOf

Introduced in: v21.4

Returns the timezone name of a DateTime or DateTime64 value.

Syntax

Arguments

  • datetime — A value of type. DateTime or DateTime64
  • timezone — Optional. Timezone name to convert the datetime value's timezone to. String

Returned value

Returns the timezone name for datetime String

Examples

Usage example

timezoneOffset

Introduced in: v21.6

Returns the timezone offset in seconds from UTC. The function takes daylight saving time and historical timezone changes at the specified date and time into account.

Syntax

Arguments

Returned value

Returns the offset from UTC in seconds Int32

Examples

Usage example

toDayOfMonth

Introduced in: v1.1

Returns the day of the month (1-31) of a Date or DateTime.

Syntax

Arguments

Returned value

Returns the day of the month of the given date/time UInt8

Examples

Usage example

toDayOfWeek

Introduced in: v1.1

Returns the number of the day within the week of a Date or DateTime value.

The two-argument form of toDayOfWeek() enables you to specify whether the week starts on Monday or Sunday, and whether the return value should be in the range from 0 to 6 or 1 to 7.

ModeFirst day of weekRange
0Monday1-7: Monday = 1, Tuesday = 2, ..., Sunday = 7
1Monday0-6: Monday = 0, Tuesday = 1, ..., Sunday = 6
2Sunday0-6: Sunday = 0, Monday = 1, ..., Saturday = 6
3Sunday1-7: Sunday = 1, Monday = 2, ..., Saturday = 7

Syntax

Arguments

  • datetime — Date or date with time to get the day of week from. Date or Date32 or DateTime or DateTime64
  • mode — Optional. Integer specifying the week mode (0-3). Defaults to 0 if omitted. UInt8
  • timezone — Optional. Timezone to use for the conversion. String

Returned value

Returns the day of the week for the given Date or DateTime UInt8

Examples

Usage example

toDayOfYear

Introduced in: v18.4

Returns the number of the day within the year (1-366) of a Date or DateTime value.

Syntax

Arguments

Returned value

Returns the day of the year of the given Date or DateTime UInt16

Examples

Usage example

toDaysSinceYearZero

Introduced in: v23.9

For a given date, returns the number of days which have passed since 1 January 0000 in the proleptic Gregorian calendar defined by ISO 8601.

The calculation is the same as in MySQL's TO_DAYS function.

Syntax

Arguments

  • date — The date or date with time for which to calculate the number of days since year zero from. Date or Date32 or DateTime or DateTime64
  • time_zone — Time zone. String

Returned value

Returns the number of days passed since date 0000-01-01. UInt32

Examples

Calculate days since year zero

toHour

Introduced in: v1.1

Returns the hour component (0-23) of a Date or DateTime value.

Syntax

Arguments

Returned value

The hour of the given Date or DateTime value UInt8

Examples

Usage example

toISOYear

Introduced in: v18.4

Converts a date or date with time to the ISO year number.

Syntax

Arguments

Returned value

Returns the input value converted to an ISO year number. UInt16

Examples

Get ISO year from date values

toLastDayOfMonth

Introduced in: v1.1

Rounds up a date or date with time to the last day of the month.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the date of the last day of the month for the given date or date with time. Date

Examples

Round up to the last day of the month

toLastDayOfWeek

Introduced in: v23.5

Rounds a date or date with time up to the nearest Saturday or Sunday.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

  • datetime — A date or date with time to convert. Date or DateTime or Date32 or DateTime64
  • mode — Determines the first day of the week as described in the toWeek() function. Default 0. UInt8
  • timezone — Optional. The timezone to use for the conversion. If not specified, the server's timezone is used. String

Returned value

Returns the date of the nearest Saturday or Sunday, on or after the given date, depending on the mode Date or Date32 or DateTime or DateTime64

Examples

Round up to the nearest Saturday or Sunday

toMillisecond

Introduced in: v24.2

Returns the millisecond component (0-999) of a DateTime or DateTime64 value.

Syntax

Arguments

Returned value

Returns the millisecond in the minute (0 - 59) of the given Date or DateTime UInt16

Examples

Usage example

toMinute

Introduced in: v1.1

Returns the minute component (0-59) of a Date or DateTime value.

Syntax

Arguments

Returned value

Returns the minute of the hour (0 - 59) of the given Date or DateTime value UInt8

Examples

Usage example

toModifiedJulianDay

Introduced in: v21.1

Converts a Proleptic Gregorian calendar date in text form YYYY-MM-DD to a Modified Julian Day number in Int32. This function supports date from 0000-01-01 to 9999-12-31. It raises an exception if the argument cannot be parsed as a date, or the date is invalid.

Syntax

Arguments

Returned value

Returns Modified Julian Day number. Int32

Examples

Convert date to Modified Julian Day

toModifiedJulianDayOrNull

Introduced in: v21.1

Similar to toModifiedJulianDay(), but instead of raising exceptions it returns NULL.

Syntax

Arguments

Returned value

Returns the modified Julian day number for valid date, otherwise null. Nullable(Int32)

Examples

Convert date to Modified Julian Day with null handling

toMonday

Introduced in: v1.1

Rounds down a date or date with time to the Monday of the same week. Returns the date.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the date of the Monday of the same week for the given date or date with time. Date

Examples

Round down to the Monday of the week

toMonth

Introduced in: v1.1

Returns the month component (1-12) of a Date or DateTime value.

Syntax

Arguments

Returned value

Returns the month of the given date/time UInt8

Examples

Usage example

toMonthNumSinceEpoch

Introduced in: v25.3

Returns amount of months passed from year 1970

Syntax

Arguments

Returned value

Positive integer

Examples

Example

toQuarter

Introduced in: v1.1

Returns the quarter of the year (1-4) for a given Date or DateTime value.

Syntax

Arguments

Returned value

Returns the quarter of the year for the given date/time UInt8

Examples

Usage example

toRelativeDayNum

Introduced in: v1.1

Converts a date or date with time to the number of days elapsed since a certain fixed point in the past. The exact point in time is an implementation detail, and therefore this function is not intended to be used standalone. The main purpose of the function is to calculate the difference in days between two dates or dates with time, e.g., toRelativeDayNum(dt1) - toRelativeDayNum(dt2).

Syntax

Arguments

Returned value

Returns the number of days from a fixed reference point in the past. UInt32

Examples

Get relative day numbers

toRelativeHourNum

Introduced in: v1.1

Converts a date or date with time to the number of hours elapsed since a certain fixed point in the past. The exact point in time is an implementation detail, and therefore this function is not intended to be used standalone. The main purpose of the function is to calculate the difference in hours between two dates or dates with time, e.g., toRelativeHourNum(dt1) - toRelativeHourNum(dt2).

Syntax

Arguments

Returned value

Returns the number of hours from a fixed reference point in the past. UInt32

Examples

Get relative hour numbers

toRelativeMinuteNum

Introduced in: v1.1

Converts a date or date with time to the number of minutes elapsed since a certain fixed point in the past. The exact point in time is an implementation detail, and therefore this function is not intended to be used standalone. The main purpose of the function is to calculate the difference in minutes between two dates or dates with time, e.g., toRelativeMinuteNum(dt1) - toRelativeMinuteNum(dt2).

Syntax

Arguments

Returned value

Returns the number of minutes from a fixed reference point in the past. UInt32

Examples

Get relative minute numbers

toRelativeMonthNum

Introduced in: v1.1

Converts a date or date with time to the number of months elapsed since a certain fixed point in the past. The exact point in time is an implementation detail, and therefore this function is not intended to be used standalone. The main purpose of the function is to calculate the difference in months between two dates or dates with time, e.g., toRelativeMonthNum(dt1) - toRelativeMonthNum(dt2).

Syntax

Arguments

Returned value

Returns the number of months from a fixed reference point in the past. UInt32

Examples

Get relative month numbers

toRelativeQuarterNum

Introduced in: v1.1

Converts a date or date with time to the number of quarters elapsed since a certain fixed point in the past. The exact point in time is an implementation detail, and therefore this function is not intended to be used standalone. The main purpose of the function is to calculate the difference in quarters between two dates or dates with time, e.g., toRelativeQuarterNum(dt1) - toRelativeQuarterNum(dt2).

Syntax

Arguments

Returned value

Returns the number of quarters from a fixed reference point in the past. UInt32

Examples

Get relative quarter numbers

toRelativeSecondNum

Introduced in: v1.1

Converts a date or date with time to the number of seconds elapsed since a certain fixed point in the past. The exact point in time is an implementation detail, and therefore this function is not intended to be used standalone. The main purpose of the function is to calculate the difference in seconds between two dates or dates with time, e.g., toRelativeSecondNum(dt1) - toRelativeSecondNum(dt2).

Syntax

Arguments

Returned value

Returns the number of seconds from a fixed reference point in the past. UInt32

Examples

Get relative second numbers

toRelativeWeekNum

Introduced in: v1.1

Converts a date or date with time to the number of weeks elapsed since a certain fixed point in the past. The exact point in time is an implementation detail, and therefore this function is not intended to be used standalone. The main purpose of the function is to calculate the difference in weeks between two dates or dates with time, e.g., toRelativeWeekNum(dt1) - toRelativeWeekNum(dt2).

Syntax

Arguments

Returned value

Returns the number of weeks from a fixed reference point in the past. UInt32

Examples

Get relative week numbers

toRelativeYearNum

Introduced in: v1.1

Converts a date or date with time to the number of years elapsed since a certain fixed point in the past. The exact point in time is an implementation detail, and therefore this function is not intended to be used standalone. The main purpose of the function is to calculate the difference in years between two dates or dates with time, e.g., toRelativeYearNum(dt1) - toRelativeYearNum(dt2).

Syntax

Arguments

Returned value

Returns the number of years from a fixed reference point in the past. UInt16

Examples

Get relative year numbers

toSecond

Introduced in: v1.1

Returns the second component (0-59) of a Date or DateTime value.

Syntax

Arguments

Returned value

Returns the second in the minute (0 - 59) of the given Date or DateTime value UInt8

Examples

Usage example

toStartOfDay

Introduced in: v1.1

Rounds down a date with time to the start of the day.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

  • datetime — A date or date with time to round. Date or DateTime

Returned value

Returns the date with time rounded down to the start of the day. Date or DateTime or Date32 or DateTime64

Examples

Round down to the start of the day

toStartOfFifteenMinutes

Introduced in: v1.1

Rounds down the date with time to the start of the fifteen-minute interval.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the date with time rounded to the start of the nearest fifteen-minute interval DateTime or DateTime64

Examples

Example

toStartOfFiveMinutes

Introduced in: v22.6

Rounds down a date with time to the start of the nearest five-minute interval.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the date with time rounded to the start of the nearest five-minute interval DateTime or DateTime64

Examples

Example

toStartOfHour

Introduced in: v1.1

Rounds down a date with time to the start of the hour.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the date with time rounded down to the start of the hour. DateTime or DateTime64

Examples

Round down to the start of the hour

toStartOfISOYear

Introduced in: v1.1

Rounds down a date or date with time to the first day of the ISO year, which can be different than a regular year. See ISO week date.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the first day of the ISO year for the given date or date with time. Date

Examples

Round down to the first day of the ISO year

toStartOfInterval

Introduced in: v20.1

This function generalizes other toStartOf*() functions with toStartOfInterval(date_or_date_with_time, INTERVAL x unit [, time_zone]) syntax.

For example,

  • toStartOfInterval(t, INTERVAL 1 YEAR) returns the same as toStartOfYear(t),
  • toStartOfInterval(t, INTERVAL 1 MONTH) returns the same as toStartOfMonth(t),
  • toStartOfInterval(t, INTERVAL 1 DAY) returns the same as toStartOfDay(t),
  • toStartOfInterval(t, INTERVAL 15 MINUTE) returns the same as toStartOfFifteenMinutes(t).

The calculation is performed relative to specific points in time:

IntervalStart
YEARyear 0
QUARTER1900 Q1
MONTH1900 January
WEEK1970, 1st week (01-05)
DAY1970-01-01
HOUR(*)
MINUTE1970-01-01 00:00:00
SECOND1970-01-01 00:00:00
MILLISECOND1970-01-01 00:00:00
MICROSECOND1970-01-01 00:00:00
NANOSECOND1970-01-01 00:00:00
(*) hour intervals are special: the calculation is always performed relative to 00:00:00 (midnight) of the current day. As a result, only
hour values between 1 and 23 are useful.

If unit WEEK was specified, toStartOfInterval assumes that weeks start on Monday. Note that this behavior is different from that of function toStartOfWeek in which weeks start by default on Sunday.

The second overload emulates TimescaleDB's time_bucket() function, respectively PostgreSQL's date_bin() function.

Syntax

Arguments

  • value — Date or date with time value to round down. Date or DateTime or DateTime64
  • x — Interval length number. - unit — Interval unit: YEAR, QUARTER, MONTH, WEEK, DAY, HOUR, MINUTE, SECOND, MILLISECOND, MICROSECOND, NANOSECOND. - time_zone — Optional. Time zone name as a string. - origin — Optional. Origin point for calculation (second overload only).

Returned value

Returns the start of the interval containing the input value. DateTime

Examples

Basic interval rounding

Using origin point

toStartOfMicrosecond

Introduced in: v22.6

Rounds down a date with time to the start of the microseconds.

Syntax

Arguments

  • datetime — Date and time. DateTime64
  • timezone — Optional. Timezone for the returned value. If not specified, the function uses the timezone of the value parameter. String

Returned value

Input value with sub-microseconds DateTime64

Examples

Query without timezone

Query with timezone

toStartOfMillisecond

Introduced in: v22.6

Rounds down a date with time to the start of the milliseconds.

Syntax

Arguments

  • datetime — Date and time. DateTime64
  • timezone — Optional. Timezone for the returned value. If not specified, the function uses the timezone of the value parameter. String

Returned value

Input value with sub-milliseconds. DateTime64

Examples

Query without timezone

Query with timezone

toStartOfMinute

Introduced in: v1.1

Rounds down a date with time to the start of the minute.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the date with time rounded down to the start of the minute. DateTime or DateTime64

Examples

Round down to the start of the minute

toStartOfMonth

Introduced in: v1.1

Rounds down a date or date with time to the first day of the month.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the first day of the month for the given date or date with time. Date

Examples

Round down to the first day of the month

toStartOfNanosecond

Introduced in: v22.6

Rounds down a date with time to the start of the nanoseconds.

Syntax

Arguments

  • datetime — Date and time. DateTime64
  • timezone — Optional. Timezone for the returned value. If not specified, the function uses the timezone of the value parameter. String

Returned value

Input value with nanoseconds. DateTime64

Examples

Query without timezone

Query with timezone

toStartOfQuarter

Introduced in: v1.1

Rounds down a date or date with time to the first day of the quarter. The first day of the quarter is either 1 January, 1 April, 1 July, or 1 October.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the first day of the quarter for the given date or date with time. Date

Examples

Round down to the first day of the quarter

toStartOfSecond

Introduced in: v20.5

Rounds down a date with time to the start of the seconds.

Syntax

Arguments

  • datetime — Date and time to truncate sub-seconds from. DateTime64
  • timezone — Optional. Timezone for the returned value. If not specified, the function uses the timezone of the value parameter. String

Returned value

Returns the input value without sub-seconds. DateTime64

Examples

Query without timezone

Query with timezone

toStartOfTenMinutes

Introduced in: v20.1

Rounds down a date with time to the start of the nearest ten-minute interval.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the date with time rounded to the start of the nearest ten-minute interval DateTime or DateTime64

Examples

Example

toStartOfWeek

Introduced in: v20.1

Rounds a date or date with time down to the nearest Sunday or Monday.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

  • datetime — A date or date with time to convert. Date or DateTime or Date32 or DateTime64
  • mode — Determines the first day of the week as described in the toWeek() function. Default 0. UInt8
  • timezone — The timezone to use for the conversion. If not specified, the server's timezone is used. String

Returned value

Returns the date of the nearest Sunday or Monday on, or prior to, the given date, depending on the mode Date or Date32 or DateTime or DateTime64

Examples

Round down to the nearest Sunday or Monday

toStartOfYear

Introduced in: v1.1

Rounds down a date or date with time to the first day of the year. Returns the date as a Date object.

Note

The return type can be configured by setting enable_extended_results_for_datetime_functions.

Syntax

Arguments

Returned value

Returns the first day of the year for the given date/time Date

Examples

Round down to the first day of the year

toTimeWithFixedDate

Introduced in: v1.1

Extracts the time component of a date or date with time. The returned result is an offset to a fixed point in time, currently 1970-01-02, but the exact point in time is an implementation detail which may change in future.

toTime should therefore not be used standalone. The main purpose of the function is to calculate the time difference between two dates or dates with time, e.g., toTime(dt1) - toTime(dt2).

Syntax

Arguments

Returned value

Returns the time component of a date or date with time in the form of an offset to a fixed point in time (selected as 1970-01-02, currently). DateTime

Examples

Calculate the time difference between two dates

toTimezone

Introduced in: v1.1

Converts a DateTime or DateTime64 to the specified time zone. The internal value (number of unix seconds) of the data doesn't change. Only the value's time zone attribute and the value's string representation changes.

Syntax

Arguments

Returned value

Returns the same timestamp as the input, but with the specified time zone DateTime or DateTime64

Examples

Usage example

toUTCTimestamp

Introduced in: v23.8

Converts a date or date with time value from one time zone to UTC timezone timestamp. This function is mainly included for compatibility with Apache Spark and similar frameworks.

Syntax

Arguments

  • datetime — A date or date with time type const value or an expression. DateTime or DateTime64
  • time_zone — A String type const value or an expression representing the time zone. String

Returned value

Returns a date or date with time in UTC timezone. DateTime or DateTime64

Examples

Convert timezone to UTC

toUnixTimestamp

Introduced in: v1.1

Converts a String, Date, or DateTime to a Unix timestamp (seconds since 1970-01-01 00:00:00 UTC) as UInt32.

Syntax

Arguments

Returned value

Returns the Unix timestamp as UInt32

Examples

Usage example

toWeek

Introduced in: v20.1

This function returns the week number for date or datetime. The two-argument form of toWeek() enables you to specify whether the week starts on Sunday or Monday and whether the return value should be in the range from 0 to 53 or from 1 to 53.

toISOWeek() is a compatibility function that is equivalent to toWeek(date,3).

The following table describes how the mode argument works.

ModeFirst day of weekRangeWeek 1 is the first week ...
0Sunday0-53with a Sunday in this year
1Monday0-53with 4 or more days this year
2Sunday1-53with a Sunday in this year
3Monday1-53with 4 or more days this year
4Sunday0-53with 4 or more days this year
5Monday0-53with a Monday in this year
6Sunday1-53with 4 or more days this year
7Monday1-53with a Monday in this year
8Sunday1-53contains January 1
9Monday1-53contains January 1

For mode values with a meaning of "with 4 or more days this year," weeks are numbered according to ISO 8601:1988:

  • If the week containing January 1 has 4 or more days in the new year, it is week 1.
  • Otherwise, it is the last week of the previous year, and the next week is week 1.

For mode values with a meaning of "contains January 1", the week contains January 1 is week 1. It does not matter how many days in the new year the week contained, even if it contained only one day. I.e. if the last week of December contains January 1 of the next year, it will be week 1 of the next year.

The first argument can also be specified as String in a format supported by parseDateTime64BestEffort(). Support for string arguments exists only for reasons of compatibility with MySQL which is expected by certain 3rd party tools. As string argument support may in future be made dependent on new MySQL-compatibility settings and because string parsing is generally slow, it is recommended to not use it.

Syntax

Arguments

  • datetime — Date or date with time to get the week number from. Date or DateTime
  • mode — Optional. A mode 0 to 9 determines the first day of the week and the range of the week number. Default 0. - time_zone — Optional. Time zone. String

Returned value

Returns the week number according to the specified mode. UInt32

Examples

Get week numbers with different modes

toYYYYMM

Introduced in: v1.1

Converts a date or date with time to a UInt32 number containing the year and month number (YYYY * 100 + MM). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.

This function is the opposite of function YYYYMMDDToDate().

Syntax

Arguments

  • datetime — A date or date with time to convert. Date or Date32 or DateTime or DateTime64
  • timezone — Optional. Timezone for the conversion. If provided, the timezone must be a string constant. String

Returned value

Returns a UInt32 number containing the year and month number (YYYY * 100 + MM). UInt32

Examples

Convert current date to YYYYMM format

toYYYYMMDD

Introduced in: v1.1

Converts a date or date with time to a UInt32 number containing the year and month number (YYYY * 10000 + MM * 100 + DD). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.

Syntax

Arguments

  • datetime — A date or date with time to convert. Date or Date32 or DateTime or DateTime64
  • timezone — Optional. Timezone for the conversion. If provided, the timezone must be a string constant. String

Returned value

Returns a UInt32 number containing the year, month and day (YYYY * 10000 + MM * 100 + DD). UInt32

Examples

Convert current date to YYYYMMDD format

toYYYYMMDDhhmmss

Introduced in: v1.1

Converts a date or date with time to a UInt64 number containing the year and month number (YYYY * 10000000000 + MM * 100000000 + DD * 1000000 + hh * 10000 + mm * 100 + ss). Accepts a second optional timezone argument. If provided, the timezone must be a string constant.

Syntax

Arguments

  • datetime — Date or date with time to convert. Date or Date32 or DateTime or DateTime64
  • timezone — Optional. Timezone for the conversion. If provided, the timezone must be a string constant. String

Returned value

Returns a UInt64 number containing the year, month, day, hour, minute and second (YYYY * 10000000000 + MM * 100000000 + DD * 1000000 + hh * 10000 + mm * 100 + ss). UInt64

Examples

Convert current date and time to YYYYMMDDhhmmss format

toYear

Introduced in: v1.1

Returns the year component (AD) of a Date or DateTime value.

Syntax

Arguments

Returned value

Returns the year of the given Date or DateTime UInt16

Examples

Usage example

toYearNumSinceEpoch

Introduced in: v25.3

Returns amount of years passed from year 1970

Syntax

Arguments

Returned value

Positive integer

Examples

Example

toYearWeek

Introduced in: v20.1

Returns the year and week for a date. The year in the result may be different from the year in the date argument for the first and the last week of the year.

The mode argument works like the mode argument of toWeek().

Warning: The week number returned by toYearWeek() can be different from what the toWeek() returns. toWeek() always returns week number in the context of the given year, and in case toWeek() returns 0, toYearWeek() returns the value corresponding to the last week of previous year. See prev_yearWeek in example below.

The first argument can also be specified as String in a format supported by parseDateTime64BestEffort(). Support for string arguments exists only for reasons of compatibility with MySQL which is expected by certain 3rd party tools. As string argument support may in future be made dependent on new MySQL-compatibility settings and because string parsing is generally slow, it is recommended to not use it.

Syntax

Arguments

  • datetime — Date or date with time to get the year and week of. Date or DateTime
  • mode — Optional. A mode 0 to 9 determines the first day of the week and the range of the week number. Default 0. - timezone — Optional. Time zone. String

Returned value

Returns year and week number as a combined integer value. UInt32

Examples

Get year-week combinations with different modes

today

Introduced in: v1.1

Returns the current date at moment of query analysis. Same as toDate(now()).

Syntax

Arguments

  • None. Returned value

Returns the current date Date

Examples

Usage example

yesterday

Introduced in: v1.1

Accepts zero arguments and returns yesterday's date at one of the moments of query analysis.

Syntax

Arguments

  • None. Returned value

Returns yesterday's date. Date

Examples

Get yesterday's date