diff --git a/docs/en/12-taos-sql/22-meta.md b/docs/en/12-taos-sql/22-meta.md index 9bda5a0a10..0a59777946 100644 --- a/docs/en/12-taos-sql/22-meta.md +++ b/docs/en/12-taos-sql/22-meta.md @@ -11,7 +11,15 @@ TDengine includes a built-in database named `INFORMATION_SCHEMA` to provide acce 4. Future versions of TDengine can add new columns to INFORMATION_SCHEMA tables without affecting existing business systems. 5. It is easier for users coming from other database management systems. For example, Oracle users can query data dictionary tables. -Note: SHOW statements are still supported for the convenience of existing users. +:::info + +- SHOW statements are still supported for the convenience of existing users. +- Some columns in the system table may be keywords, and you need to use the escape character '\`' when querying, for example, to query the VGROUPS in the database `test`: +```sql + select `vgroups` from ins_databases where name = 'test'; +``` + +::: This document introduces the tables of INFORMATION_SCHEMA and their structure. @@ -102,7 +110,11 @@ Provides information about user-created databases. Similar to SHOW DATABASES. | 24 | wal_retention_period | INT | WAL retention period | | 25 | wal_retention_size | INT | Maximum WAL size | | 26 | wal_roll_period | INT | WAL rotation period | -| 27 | wal_segment_size | WAL file size | +| 27 | wal_segment_size | BIGINT | WAL file size | +| 28 | stt_trigger | SMALLINT | The threshold for number of files to trigger file merging | +| 29 | table_prefix | SMALLINT | The prefix length in the table name that is ignored when distributing table to vnode based on table name | +| 30 | table_suffix | SMALLINT | The suffix length in the table name that is ignored when distributing table to vnode based on table name | +| 31 | tsdb_pagesize | INT | The page size for internal storage engine, its unit is KB | ## INS_FUNCTIONS diff --git a/docs/zh/12-taos-sql/22-meta.md b/docs/zh/12-taos-sql/22-meta.md index c1ffc4a757..c192d0e5e8 100644 --- a/docs/zh/12-taos-sql/22-meta.md +++ b/docs/zh/12-taos-sql/22-meta.md @@ -12,7 +12,15 @@ TDengine 内置了一个名为 `INFORMATION_SCHEMA` 的数据库,提供对数 4. TDengine 在后续演进中可以灵活的添加已有 INFORMATION_SCHEMA 中表的列,而不用担心对既有业务系统造成影响 5. 与其他数据库系统更具互操作性。例如,Oracle 数据库用户熟悉查询 Oracle 数据字典中的表 -Note: 由于 SHOW 语句已经被开发者熟悉和广泛使用,所以它们仍然被保留。 +:::info + +- 由于 SHOW 语句已经被开发者熟悉和广泛使用,所以它们仍然被保留。 +- 系统表中的一些列可能是关键字,在查询时需要使用转义符'\`',例如查询数据库 test 有几个 VGROUP: +```sql + select `vgroups` from ins_databases where name = 'test'; +``` + +::: 本章将详细介绍 `INFORMATION_SCHEMA` 这个内置元数据库中的表和表结构。 @@ -103,7 +111,11 @@ Note: 由于 SHOW 语句已经被开发者熟悉和广泛使用,所以它们 | 24 | wal_retention_period | INT | WAL 的保存时长 | | 25 | wal_retention_size | INT | WAL 的保存上限 | | 26 | wal_roll_period | INT | wal 文件切换时长 | -| 27 | wal_segment_size | wal 单个文件大小 | +| 27 | wal_segment_size | BIGINT | wal 单个文件大小 | +| 28 | stt_trigger | SMALLINT | 触发文件合并的落盘文件的个数 | +| 29 | table_prefix | SMALLINT | 内部存储引擎根据表名分配存储该表数据的 VNODE 时要忽略的前缀的长度 | +| 30 | table_suffix | SMALLINT | 内部存储引擎根据表名分配存储该表数据的 VNODE 时要忽略的后缀的长度 | +| 31 | tsdb_pagesize | INT | 时序数据存储引擎中的页大小 | ## INS_FUNCTIONS