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Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@ title: Fuse Engine 表

import FunctionDescription from '@site/src/components/FunctionDescription';

<FunctionDescription description="Introduced or updated: v1.2.736"/>
<FunctionDescription description="Introduced or updated: v1.2.892"/>

## 概述

Expand Down Expand Up @@ -126,6 +126,29 @@ CREATE TABLE <table_name> (

---

### `bloom_index_type`

- **语法:**
`bloom_index_type = 'xor8' | 'binary_fuse32'`
- **描述:**
指定 Bloom Index 使用的过滤器算法类型。默认为 `xor8`。对于有大量点查(point lookup)的表,推荐使用 `binary_fuse32`,它具有更低的误判率,但索引体积约为 `xor8` 的 4 倍。

注意:`ALTER TABLE ... SET OPTIONS(bloom_index_type = ...)` 只影响新写入的数据和重建的 Bloom Index,已有的 `xor8` 格式索引文件与新的 `binary_fuse32` 索引文件可以在同一张表中共存。

**示例:**
```sql
-- 建表时指定 bloom_index_type
CREATE TABLE t (a INT) bloom_index_type = 'binary_fuse32';

-- 修改已有表的 bloom_index_type(只影响后续写入)
ALTER TABLE t SET OPTIONS(bloom_index_type = 'binary_fuse32');

-- 改回 xor8
ALTER TABLE t SET OPTIONS(bloom_index_type = 'xor8');
```

---

### `change_tracking`

- **语法:**
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@ title: Fuse Engine Tables

import FunctionDescription from '@site/src/components/FunctionDescription';

<FunctionDescription description="Introduced or updated: v1.2.736"/>
<FunctionDescription description="Introduced or updated: v1.2.892"/>

## Overview

Expand Down Expand Up @@ -117,6 +117,28 @@ Below are the available Fuse Engine options, grouped by their purpose:

---

### `bloom_index_type`
- **Syntax:**
`bloom_index_type = 'xor8' | 'binary_fuse32'`
- **Description:**
Specifies the filter algorithm used for the bloom index. Defaults to `xor8`. Use `binary_fuse32` for tables with heavy point-lookup workloads — it offers a lower false-positive rate at the cost of a larger index size (approximately 4x that of `xor8`).

Note that `ALTER TABLE ... SET OPTIONS(bloom_index_type = ...)` only affects new writes and rebuilt bloom indexes. Existing `xor8` index files and new `binary_fuse32` index files can coexist in the same table.

**Examples:**
```sql
-- Set bloom_index_type at table creation
CREATE TABLE t (a INT) bloom_index_type = 'binary_fuse32';

-- Change bloom_index_type for an existing table (affects new writes only)
ALTER TABLE t SET OPTIONS(bloom_index_type = 'binary_fuse32');

-- Revert to xor8
ALTER TABLE t SET OPTIONS(bloom_index_type = 'xor8');
```

---

### `change_tracking`
- **Syntax:**
`change_tracking = True / False`
Expand Down
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