SHOW

SHOW 关键字提供数据库和表信息。

SHOW DATABASES

展示所有数据库：

SHOW DATABASES;

+---------+
| Schemas |
+---------+
| public  |
+---------+
1 row in set (0.01 sec)

展示名称符合 LIKE 模式的数据库：

SHOW DATABASES LIKE 'p%';

根据 where 表达式展示数据库：

SHOW DATABASES WHERE Schemas='test_public_schema';

SHOW TABLES

展示所有表：

SHOW TABLES;

+---------+
| Tables  |
+---------+
| numbers |
| scripts |
+---------+
2 rows in set (0.00 sec)

展示 test 数据库中的所有表：

SHOW TABLES FROM test;

展示名称符合 LIKE 模式的表：

SHOW TABLES like '%prometheus%';

根据 where 表达式展示表：

SHOW TABLES FROM test WHERE Tables='numbers';

SHOW FULL TABLES

SHOW FULL TABLES [IN | FROM] [DATABASE] [LIKE pattern] [WHERE query]

将会展示指定数据库（或者默认 public）中所有的表及其类型：

SHOW FULL TABLES;

+---------+------------+
| Tables  | Table_type |
+---------+------------+
| monitor | BASE TABLE |
| numbers | TEMPORARY  |
+---------+------------+
2 rows in set (0.00 sec)

• Tables: 表的名称
• Table_type: 表的类型，例如 BASE_TABLE, TEMPORARY 和 VIEW 等等。

同样也支持 like 和 where 查询：

SHOW FULL TABLES FROM public like '%mo%';

+---------+------------+
| Tables  | Table_type |
+---------+------------+
| monitor | BASE TABLE |
+---------+------------+
1 row in set (0.01 sec)

SHOW FULL TABLES WHERE Table_type='BASE TABLE';

+---------+------------+
| Tables  | Table_type |
+---------+------------+
| monitor | BASE TABLE |
+---------+------------+
1 row in set (0.01 sec)

SHOW CREATE TABLE

展示创建指定表的 CREATE TABLE 语句：

SHOW CREATE TABLE [table]

例如：

SHOW CREATE TABLE system_metrics;

+----------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table          | Create Table                                                                                                                                                                                                                                                                                                                 |
+----------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| system_metrics | CREATE TABLE IF NOT EXISTS `system_metrics` (
  `host` STRING NULL,
  `idc` STRING NULL,
  `cpu_util` DOUBLE NULL,
  `memory_util` DOUBLE NULL,
  `disk_util` DOUBLE NULL,
  `ts` TIMESTAMP(3) NOT NULL DEFAULT current_timestamp(),
  TIME INDEX (`ts`),
  PRIMARY KEY (`host`, `idc`)
)

ENGINE=mito
WITH(
  regions = 1
) |
+----------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

• Table: 表的名称
• Create Table: 用于创建该表的 SQL