> ## Documentation Index
> Fetch the complete documentation index at: https://clickhouse.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# mysql_* session settings

> ClickHouse session settings in the mysql_* generated group.

export const SettingsInfoBlock = ({type, default_value, changeable_without_restart}) => {
  return <div className="not-prose" style={{
    display: "flex",
    flexWrap: "wrap",
    alignItems: "baseline",
    columnGap: "0.5rem",
    rowGap: "0.125rem",
    margin: "0.375rem 0",
    fontSize: "0.8125rem",
    lineHeight: "1.125rem"
  }}>
      <div style={{
    fontWeight: 600,
    opacity: 0.72
  }}>Type</div>
      <div style={{
    overflowWrap: "anywhere"
  }}>{type}</div>
      <div style={{
    fontWeight: 600,
    opacity: 0.72,
    marginInlineStart: "0.5rem"
  }}>Default</div>
      <div style={{
    overflowWrap: "anywhere"
  }}>{default_value}</div>
      {changeable_without_restart && <div style={{
    fontWeight: 600,
    opacity: 0.72,
    marginInlineStart: "0.5rem"
  }}>
          Changeable without restart
        </div>}
      {changeable_without_restart && <div style={{
    overflowWrap: "anywhere"
  }}>
          {changeable_without_restart}
        </div>}
    </div>;
};

These settings are available in [system.settings](/docs/reference/system-tables/settings) and are autogenerated from [source](https://github.com/ClickHouse/ClickHouse/blob/master/src/Core/Settings.cpp).

<h2 id="mysql_datatypes_support_level">
  mysql\_datatypes\_support\_level
</h2>

<SettingsInfoBlock type="MySQLDataTypesSupport" default_value="decimal,datetime64,date2Date32,geometry" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "26.7"},{"label": "decimal,datetime64,date2Date32,geometry"},{"label": "Map MySQL's concrete spatial types (LINESTRING, POLYGON, MULTILINESTRING, MULTIPOLYGON) and the generic GEOMETRY type to the corresponding ClickHouse geometric types by default. The generic GEOMETRY column maps to the umbrella Geometry type; reading a value whose subtype has no ClickHouse counterpart (MULTIPOINT, GEOMETRYCOLLECTION) throws at read time."}]}, {"id": "row-2","items": [{"label": "26.3"},{"label": "decimal,datetime64,date2Date32"},{"label": "Enable modern MySQL type mappings by default."}]}]} />

Defines how MySQL types are converted to corresponding ClickHouse types. A comma separated list in any combination of `decimal`, `datetime64`, `date2Date32`, `date2String` or `geometry`. All modern mappings (`decimal`, `datetime64`, `date2Date32`, `geometry`) are enabled by default.

* `decimal`: convert `NUMERIC` and `DECIMAL` types to `Decimal` when precision allows it.
* `datetime64`: convert `DATETIME` and `TIMESTAMP` types to `DateTime64` instead of `DateTime` when precision is not `0`.
* `date2Date32`: convert `DATE` to `Date32` instead of `Date`. Takes precedence over `date2String`.
* `date2String`: convert `DATE` to `String` instead of `Date`. Overridden by `datetime64`.
* `geometry`: convert MySQL's spatial types (`LINESTRING`, `POLYGON`, `MULTILINESTRING`, `MULTIPOLYGON`) to the corresponding ClickHouse geometric types, and the generic `GEOMETRY` type to the umbrella `Geometry` type. `POINT` is always converted to `Point` regardless of this option. Because a generic `GEOMETRY` column can hold any subtype, reading a value whose subtype has no ClickHouse counterpart (`MULTIPOINT`, `GEOMETRYCOLLECTION`) throws an exception at read time; columns declared as `MULTIPOINT` or `GEOMETRYCOLLECTION` map to `String`.

<h2 id="mysql_max_rows_to_insert">
  mysql\_max\_rows\_to\_insert
</h2>

<SettingsInfoBlock type="UInt64" default_value="65536" />

The maximum number of rows in MySQL batch insertion of the MySQL storage engine