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6 changes: 6 additions & 0 deletions .gitignore
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Expand Up @@ -18,3 +18,9 @@ build
.temp_patch

Claude.md

# Transpiled JavaScript files (TypeScript sources are tracked)
docusaurus.config.js
sidebars.js
src/**/*.js
variables/*.js
29 changes: 29 additions & 0 deletions docs/reference/sql/alter.md
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Expand Up @@ -32,6 +32,9 @@ Currently following options are supported:
- If `ttl` was not previously set, defining a new `ttl` using `ALTER` will result in the deletion of data that exceeds the specified retention time.
- If `ttl` was already set, modifying it via `ALTER` will enforce the updated retention time immediately, removing data that exceeds the new retention threshold.
- If `ttl` was previously set and is unset using `ALTER`, new data will no longer be deleted. However, data that was previously deleted due to the retention policy cannot be restored.
- `compaction.twcs.time_window`: the time window parameter of TWCS compaction strategy. The value should be a [time duration string](/reference/time-durations.md).
- `compaction.twcs.max_output_file_size`: the maximum allowed output file size of TWCS compaction strategy.
- `compaction.twcs.trigger_file_num`: the number of files in a specific time window to trigger a compaction.

### Examples

Expand All @@ -49,6 +52,32 @@ Remove the default retention time of data in the database:
ALTER DATABASE db UNSET 'ttl';
```

#### Modify compaction options of database

Change the compaction time window for the database:

```sql
ALTER DATABASE db SET 'compaction.twcs.time_window'='2h';
```

Change the maximum output file size for compaction:

```sql
ALTER DATABASE db SET 'compaction.twcs.max_output_file_size'='500MB';
```

Change the trigger file number for compaction:

```sql
ALTER DATABASE db SET 'compaction.twcs.trigger_file_num'='8';
```

Remove compaction options:

```sql
ALTER DATABASE db UNSET 'compaction.twcs.time_window';
```

## ALTER TABLE

### Syntax
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Expand Up @@ -32,6 +32,9 @@ ALTER DATABASE db
- 如果之前未设置 ttl,通过 `ALTER` 设置新的 ttl 后,超过保留时间的数据将被删除。
- 如果之前已设置过 ttl,通过 `ALTER` 修改 ttl 后,新的保留时间将立即生效,超过新保留时间的数据将被删除。
- 如果之前已设置过 ttl,通过 `ALTER` 取消 ttl 设置后,新增的数据将不会被删除,但已被删除的数据无法恢复。
- `compaction.twcs.time_window`: TWCS 压缩策略的时间窗口参数。值应该是一个[时间长度字符串](/reference/time-durations.md)。
- `compaction.twcs.max_output_file_size`: TWCS 压缩策略的最大允许输出文件大小。
- `compaction.twcs.trigger_file_num`: 触发压缩的特定时间窗口中的文件数。

### 示例

Expand All @@ -49,6 +52,32 @@ ALTER DATABASE db SET 'ttl'='1d';
ALTER DATABASE db UNSET 'ttl';
```

#### 修改数据库的压缩选项

修改数据库的压缩时间窗口:

```sql
ALTER DATABASE db SET 'compaction.twcs.time_window'='2h';
```

修改压缩的最大输出文件大小:

```sql
ALTER DATABASE db SET 'compaction.twcs.max_output_file_size'='500MB';
```

修改触发压缩的文件数:

```sql
ALTER DATABASE db SET 'compaction.twcs.trigger_file_num'='8';
```

取消压缩选项:

```sql
ALTER DATABASE db UNSET 'compaction.twcs.time_window';
```

## ALTER TABLE

## 语法
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