> ## Documentation Index
> Fetch the complete documentation index at: https://private-7c7dfe99-revert-104359-revert-104251-parquet-single.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# use_statistics_* session settings

> ClickHouse session settings in the use_statistics_* generated group.

export const VersionHistory = ({rows = []}) => {
  if (rows.length === 0) {
    return null;
  }
  const headers = ["Version", "Default value", "Comment"];
  const border = "1px solid rgba(128, 128, 128, 0.3)";
  const cell = {
    border,
    padding: "0.25rem 0.5rem",
    textAlign: "start",
    verticalAlign: "top"
  };
  return <details className="not-prose" style={{
    border,
    borderRadius: "0.5rem",
    margin: "0.5rem 0",
    padding: "0.5rem 0.75rem",
    fontSize: "0.8125rem",
    lineHeight: "1.125rem"
  }}>
      <summary style={{
    cursor: "pointer",
    fontWeight: 600,
    opacity: 0.72
  }}>
        Version history
      </summary>
      <table style={{
    borderCollapse: "collapse",
    width: "100%",
    margin: "0.5rem 0 0"
  }}>
        <thead>
          <tr>
            {headers.map(header => <th key={header} style={{
    ...cell,
    fontWeight: 600,
    opacity: 0.72
  }}>
                {header}
              </th>)}
          </tr>
        </thead>
        <tbody>
          {rows.map((row, row_index) => <tr key={row.id ?? row_index}>
              {(row.items ?? []).map((item, item_index) => <td key={item_index} style={{
    ...cell,
    overflowWrap: "anywhere"
  }}>
                  {item?.label}
                </td>)}
            </tr>)}
        </tbody>
      </table>
    </details>;
};

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

<h2 id="use_statistics">
  use\_statistics
</h2>

<SettingsInfoBlock type="Bool" default_value="1" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "26.1"},{"label": "1"},{"label": "Enable this optimization by default."}]}]} />

/// preferred over 'allow\_statistics\_optimize' because of consistency with 'use\_primary\_key' and 'use\_skip\_indexes'
Allows using statistics to optimize queries

<h2 id="use_statistics_cache">
  use\_statistics\_cache
</h2>

<SettingsInfoBlock type="Bool" default_value="1" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "26.2"},{"label": "1"},{"label": "Enable statistics cache"}]}, {"id": "row-2","items": [{"label": "25.11"},{"label": "0"},{"label": "New setting"}]}]} />

Use statistics cache in a query to avoid the overhead of loading statistics of every parts

<h2 id="use_statistics_for_min_max_aggregation">
  use\_statistics\_for\_min\_max\_aggregation
</h2>

<SettingsInfoBlock type="Bool" default_value="1" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "26.9"},{"label": "1"},{"label": "New setting to answer `min`, `max` and `count` aggregations without `GROUP BY` and filters from per-part column statistics for parts that have them materialized, reading only the remaining parts. previous_value=false so `compatibility` with versions before 26.9 keeps the optimization disabled and restores the pre-existing plan."}]}]} />

Answer `min`, `max` and `count` aggregations from per-part column statistics instead of reading data.

When enabled, a query of the form `SELECT min(column), max(column), count() FROM table` without `GROUP BY` and filters
is answered from column statistics (e.g. MinMax statistics, see the `auto_statistics_types` MergeTree setting)
for the data parts that have them materialized, and only the remaining parts are read.

Possible values:

* 0 — Disabled.
* 1 — Enabled.

<h2 id="use_statistics_for_part_pruning">
  use\_statistics\_for\_part\_pruning
</h2>

<SettingsInfoBlock type="Bool" default_value="1" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "26.4"},{"label": "1"},{"label": "New setting to use statistics for part pruning during query execution."}]}]} />

Use statistics to filter out parts during query execution.

When enabled, pruning in SELECT queries will use column statistics (e.g. MinMax statistics) to eliminate parts that cannot contain matching data before reading any data.

Possible values:

* 0 — Disabled.
* 1 — Enabled.