> ## 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.

# async_* MergeTree 表设置

> ClickHouse 在 async_* 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>;
};

这些设置位于 [system.merge\_tree\_settings](/docs/zh/reference/system-tables/merge_tree_settings) 中，由 ClickHouse 源代码自动生成。

<div id="async_block_ids_cache_update_wait_ms">
  ## async\_block\_ids\_cache\_update\_wait\_ms
</div>

<SettingsInfoBlock type="毫秒" default_value="100" />

`deduplication_hashes_cache_update_wait_ms` 的已弃用别名，为保持向后兼容而保留一个版本。

仅当 `deduplication_hashes_cache_update_wait_ms` 保持默认值时，此别名才会生效；该设置将在未来的版本中移除。

<div id="async_insert">
  ## async\_insert
</div>

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

如果为 true，来自 INSERT 查询的数据会先存储在队列中，随后在后台写入
表中。