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tsma hint add doc

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wangjiaming0909 2024-04-30 16:54:14 +08:00
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docs/en/12-taos-sql/06-select.md
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@ -95,6 +95,7 @@ The list of currently supported Hints is as follows:
| PARTITION_FIRST| None | Use Partition before aggregate, conflict with SORT_FOR_GROUP | With normal column in partition by list | | PARTITION_FIRST| None | Use Partition before aggregate, conflict with SORT_FOR_GROUP | With normal column in partition by list |
| PARA_TABLES_SORT| None | When sorting the supertable rows by timestamp, No temporary disk space is used. When there are numerous tables, each with long rows, the corresponding algorithm associated with this prompt may consume a substantial amount of memory, potentially leading to an Out Of Memory (OOM) situation. | Sorting the supertable rows by timestamp | | PARA_TABLES_SORT| None | When sorting the supertable rows by timestamp, No temporary disk space is used. When there are numerous tables, each with long rows, the corresponding algorithm associated with this prompt may consume a substantial amount of memory, potentially leading to an Out Of Memory (OOM) situation. | Sorting the supertable rows by timestamp |
| SMALLDATA_TS_SORT| None | When sorting the supertable rows by timestamp, if the length of query columns >= 256, and there are relatively few rows, this hint can improve performance. | Sorting the supertable rows by timestamp | | SMALLDATA_TS_SORT| None | When sorting the supertable rows by timestamp, if the length of query columns >= 256, and there are relatively few rows, this hint can improve performance. | Sorting the supertable rows by timestamp |
| SKIP_TSMA| None| To explicitly disable tsma optimization for select query|Select query with agg funcs|
For example: For example:

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docs/zh/12-taos-sql/06-select.md
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@ -95,6 +95,7 @@ Hints 是用户控制单个语句查询优化的一种手段，当 Hint 不适
| PARTITION_FIRST| 无 | 在聚合之前使用PARTITION计算分组, 与SORT_FOR_GROUP冲突 | partition by 列表有普通列时 | | PARTITION_FIRST| 无 | 在聚合之前使用PARTITION计算分组, 与SORT_FOR_GROUP冲突 | partition by 列表有普通列时 |
| PARA_TABLES_SORT| 无 | 超级表的数据按时间戳排序时, 不使用临时磁盘空间, 只使用内存。当子表数量多, 行长比较大时候, 会使用大量内存, 可能发生OOM | 超级表的数据按时间戳排序时 | | PARA_TABLES_SORT| 无 | 超级表的数据按时间戳排序时, 不使用临时磁盘空间, 只使用内存。当子表数量多, 行长比较大时候, 会使用大量内存, 可能发生OOM | 超级表的数据按时间戳排序时 |
| SMALLDATA_TS_SORT| 无 | 超级表的数据按时间戳排序时, 查询列长度大于等于256, 但是行数不多, 使用这个提示, 可以提高性能 | 超级表的数据按时间戳排序时 | | SMALLDATA_TS_SORT| 无 | 超级表的数据按时间戳排序时, 查询列长度大于等于256, 但是行数不多, 使用这个提示, 可以提高性能 | 超级表的数据按时间戳排序时 |
| SKIP_TSMA | 无 | 用于显示的禁用TSMA查询优化 | 带Agg函数的查询语句 |
举例： 举例：