> ## 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.

# enable_* MergeTree 表设置

> ClickHouse 的 enable_* 分组中的 MergeTree 表设置。

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
  }}>类型</div>
      <div style={{
    overflowWrap: "anywhere"
  }}>{type}</div>
      <div style={{
    fontWeight: 600,
    opacity: 0.72,
    marginInlineStart: "0.5rem"
  }}>默认值</div>
      <div style={{
    overflowWrap: "anywhere"
  }}>{default_value}</div>
      {changeable_without_restart && <div style={{
    fontWeight: 600,
    opacity: 0.72,
    marginInlineStart: "0.5rem"
  }}>
          无需重启即可更改
        </div>}
      {changeable_without_restart && <div style={{
    overflowWrap: "anywhere"
  }}>
          {changeable_without_restart}
        </div>}
    </div>;
};

export const ExperimentalBadge = () => {
  return <div className="experimentalBadge">
            <div className="experimentalIcon">
            <svg width="16" height="16" viewBox="0 0 16 16" fill="none" xmlns="http://www.w3.org/2000/svg">
                <path strokeWidth="1.25" d="M5.5 2H10.5" stroke="currentColor" strokeLinecap="round" strokeLinejoin="round" />
                <path strokeWidth="1.25" d="M9.50015 2V6.19625L13.4283 12.7425C13.4738 12.8183 13.4985 12.9049 13.4996 12.9934C13.5008 13.0818 13.4785 13.169 13.435 13.246C13.3914 13.323 13.3283 13.3871 13.2519 13.4317C13.1755 13.4764 13.0886 13.4999 13.0002 13.5H3.00015C2.91164 13.5 2.8247 13.4766 2.74822 13.432C2.67174 13.3874 2.60847 13.3233 2.56487 13.2463C2.52126 13.1693 2.49889 13.082 2.50004 12.9935C2.50119 12.905 2.52582 12.8184 2.5714 12.7425L6.50015 6.19625V2" stroke="currentColor" strokeLinecap="round" strokeLinejoin="round" />
                <path strokeWidth="1.25" d="M4.47656 9.56754C5.30344 9.41254 6.47656 9.47942 7.99969 10.25C10.0153 11.2707 11.4216 11.0569 12.2184 10.7282" stroke="currentColor" strokeLinecap="round" strokeLinejoin="round" />
            </svg>
        </div>
            Experimental 功能。 <u><a href="/docs/docs/beta-and-experimental-features#experimental-features">了解详情。</a></u>
        </div>;
};

这些设置可在 [system.merge\_tree\_settings](/docs/zh/reference/system-tables/merge_tree_settings) 中查看，且由 ClickHouse 源代码自动生成。

<div id="enable_index_granularity_compression">
  ## enable\_index\_granularity\_compression
</div>

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

如果可以，则压缩内存中的索引粒度值

<div id="enable_max_bytes_limit_for_min_age_to_force_merge">
  ## enable\_max\_bytes\_limit\_for\_min\_age\_to\_force\_merge
</div>

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

<VersionHistory rows={[{"id": "row-1","items": [{"label": "26.2"},{"label": "1"},{"label": "默认情况下，即使设置了 min_age_to_force_merge_seconds，也会限制 part 大小"}]}, {"id": "row-2","items": [{"label": "25.1"},{"label": "0"},{"label": "新增设置，用于限制 min_age_to_force_merge 的最大字节数。"}]}, {"id": "row-3","items": [{"label": "25.1"},{"label": "0"},{"label": "新设置"}]}]} />

设置 `min_age_to_force_merge_seconds` 和
`min_age_to_force_merge_on_partition_only` 是否应遵循
`max_bytes_to_merge_at_max_space_in_pool` 设置。

可能的值：

* `true`
* `false`

<div id="enable_mixed_granularity_parts">
  ## enable\_mixed\_granularity\_parts
</div>

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

启用或禁用切换为使用 `index_granularity_bytes` 设置来控制粒度大小。在 19.11 版本之前，只有
`index_granularity` 设置可用于限制粒度大小。`index_granularity_bytes`
设置可在从包含大行 (数十到数百 MB) 的表中读取数据时提升 ClickHouse 的性能。
如果你的表中存在大行，可以为这些表启用此设置，
以提高 `SELECT` 查询的效率。

<div id="enable_replacing_merge_with_cleanup_for_min_age_to_force_merge">
  ## enable\_replacing\_merge\_with\_cleanup\_for\_min\_age\_to\_force\_merge
</div>

<ExperimentalBadge />

<SettingsInfoBlock type="Bool" default_value="0" />

<VersionHistory rows={[{"id": "row-1","items": [{"label": "25.3"},{"label": "0"},{"label": "允许 ReplacingMergeTree 自动执行 CLEANUP 合并的新设置"}]}]} />

在将分区合并为单个 part 时，是否对 ReplacingMergeTree 使用 CLEANUP 合并。需要启用 `allow_experimental_replacing_merge_with_cleanup`、`min_age_to_force_merge_seconds` 和 `min_age_to_force_merge_on_partition_only`。

可选值：

* `true`
* `false`

<div id="enable_the_endpoint_id_with_zookeeper_name_prefix">
  ## enable\_the\_endpoint\_id\_with\_zookeeper\_name\_prefix
</div>

<SettingsInfoBlock type="Bool" default_value="0" />

为 ReplicatedMergeTree 表启用带有 ZooKeeper 名称前缀的 Endpoint ID。

<div id="enable_vertical_merge_algorithm">
  ## enable\_vertical\_merge\_algorithm
</div>

<SettingsInfoBlock type="UInt64" default_value="1" />

启用 Vertical merge algorithm。
