MySQL 或 MariaDB 查詢所有數據庫名下表格名、表格註釋、字段名、字段類型、字段註釋

1. 查詢所有數據庫名下所有表名、表註釋和所有字段名、數據類型、字段註釋

SELECT
    t.TABLE_SCHEMA AS 庫名,
    t.TABLE_NAME AS 表名,
    t.TABLE_COMMENT AS 表註釋,
    c.COLUMN_NAME AS 字段名,
    c.COLUMN_TYPE AS 數據類型,
    c.COLUMN_COMMENT AS 字段註釋
FROM
    INFORMATION_SCHEMA.TABLES AS t,
    INFORMATION_SCHEMA.COLUMNS AS c
WHERE
    c.TABLE_NAME = t.TABLE_NAME
    AND t.TABLE_SCHEMA = 'schema_name';

2. 查詢數據庫名下所有表名、表註釋

SELECT
    TABLE_NAME AS 表名,
    TABLE_COMMENT AS 表註釋
FROM
    INFORMATION_SCHEMA.TABLES
WHERE
    TABLE_SCHEMA = 'schema_name';

3. 查詢數據庫名下某個表格名下所有字段名、數據類型、字段註釋

SELECT
    COLUMN_NAME AS 字段名,
    DATA_TYPE AS 數據類型,
    COLUMN_COMMENT AS 字段註釋
FROM
    INFORMATION_SCHEMA.COLUMNS
WHERE
    TABLE_SCHEMA = 'schema_name'
    AND TABLE_NAME = 'table_name';

4. 查詢數據庫下所有表下所有字段名、數據類型、字段註釋

SELECT
    COLUMN_NAME AS 字段名,
    DATA_TYPE AS 數據類型,
    COLUMN_COMMENT AS 字段註釋
FROM
    INFORMATION_SCHEMA.COLUMNS
WHERE
    TABLE_SCHEMA = 'schema_name';

5. 查詢數據庫下所有表名、表註釋和所有字段名、數據類型、字段註釋

SELECT
    t.TABLE_NAME AS 表名,
    t.TABLE_COMMENT AS 表註釋,
    c.COLUMN_NAME AS 字段名,
    c.COLUMN_TYPE AS 數據類型,
    c.COLUMN_COMMENT AS 字段註釋
FROM
    INFORMATION_SCHEMA.TABLES AS t,
    INFORMATION_SCHEMA.COLUMNS AS c
WHERE
    c.TABLE_NAME = t.TABLE_NAME
    AND t.TABLE_SCHEMA = 'schema_name';