Selecting ClickHouse Data

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ClickHouse is a SQL database, and you query your data by writing the same type of SELECT queries you’re already familiar with. For example:

SELECT *
FROM helloworld.my_first_table
ORDER BY timestamp

View the SQL Reference for more details on the syntax and available clauses and options.

Notice the response comes back in a nice table format:

┌─user_id─┬─message────────────────────────────────────────────┬───────────timestamp─┬──metric─┐
│     102 │ Insert a lot of rows per batch                     │ 2022-03-21 00:00:00 │ 1.41421 │
│     102 │ Sort your data based on your commonly-used queries │ 2022-03-22 00:00:00 │   2.718 │
│     101 │ Hello, ClickHouse!                                 │ 2022-03-22 14:04:09 │      -1 │
│     101 │ Granules are the smallest chunks of data read      │ 2022-03-22 14:04:14 │ 3.14159 │
└─────────┴────────────────────────────────────────────────────┴─────────────────────┴─────────┘

4 rows in set. Elapsed: 0.008 sec.

Add a FORMAT clause to specify one of the many supported output formats of ClickHouse:

SELECT *
FROM helloworld.my_first_table
ORDER BY timestamp
FORMAT TabSeparated

In the above query, the output is returned as tab-separated:

Query id: 3604df1c-acfd-4117-9c56-f86c69721121

Insert a lot of rows per batch      2022-03-21 00:00:00     1.41421
Sort your data based on your commonly-used queries  2022-03-22 00:00:00     2.718
Hello, ClickHouse!  2022-03-22 14:04:09     -1
Granules are the smallest chunks of data read       2022-03-22 14:04:14     3.14159

rows in set. Elapsed: 0.005 sec.

ClickHouse supports over 70 input and output formats, so between the thousands of functions and all the data formats, you can use ClickHouse to perform some impressive and fast ETL-like data transformations. In fact, you don’t even need a ClickHouse server up and running to transform data - you can use the clickhouse-local tool. View the docs page of clickhouse-local for details.

All quickstarts

Last modified on July 8, 2026

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