1、要查询数据库 "mammothcode" 下所有表名以及表注释
/* 查询数据库 ‘mammothcode’ 所有表注释 */
SELECT TABLE_NAME,TABLE_COMMENT FROM information_schema.TABLES WHERE table_schema='mammothcode';
2、要查询表字段的注释
/* 查询数据库 ‘mammothcode’ 下表 ‘t_adminuser’ 所有字段注释 */
SELECT COLUMN_NAME,column_comment FROM INFORMATION_SCHEMA.Columns WHERE table_name='t_adminuser' AND table_schema='mammothcode'
3、一次性查询数据库 "mammothcode" 下表注释以及对应表字段注释
SELECT t.TABLE_NAME,t.TABLE_COMMENT,c.COLUMN_NAME,c.COLUMN_TYPE,c.COLUMN_COMMENT
FROM information_schema.TABLES t,INFORMATION_SCHEMA.Columns c
WHERE c.TABLE_NAME=t.TABLE_NAME AND t.`TABLE_SCHEMA`='mammothcode'
扩展：使用存储过程，对上面sql语句进行存储，SQL 如下：
DELIMITER//
DROP PROCEDURE IF EXISTS findComment//
CREATE PROCEDURE findComment (dbName VARCHAR(50))
BEGIN
DECLARE stmt VARCHAR(65535);
#如果用户名长度大于0
IF LENGTH(dbName)>0 THEN
BEGIN
SET @sqlstr=CONCAT('SELECT t.TABLE_NAME,t.TABLE_COMMENT,c.COLUMN_NAME,c.COLUMN_TYPE,c.COLUMN_COMMENT FROM information_schema.TABLES t,INFORMATION_SCHEMA.Columns c WHERE c.TABLE_NAME=t.TABLE_NAME AND t.`TABLE_SCHEMA`=','''',dbName,'''');
END;
ELSE
BEGIN
SET @sqlstr=CONCAT('SELECT ','''','数据库名不能为空','''', 'AS ','''','提示','''');
END;
END IF;
PREPARE stmt FROM @sqlstr;
EXECUTE stmt;
END//
DELIMITER ;
调用存储过程：
CALL findComment('xiyinli_test');
上面的存储过程还可以简化：在存储过程中直接查询当前使用的数据库，如下：
DELIMITER//
DROP PROCEDURE IF EXISTS findComment//
CREATE PROCEDURE findComment ()
BEGIN
DECLARE stmt VARCHAR(65535);
#查询当前的 use-->database
SET @dbName=(SELECT DATABASE());
BEGIN
SET @sqlstr=CONCAT('SELECT t.TABLE_NAME,t.TABLE_COMMENT,c.COLUMN_NAME,c.COLUMN_TYPE,c.COLUMN_COMMENT FROM information_schema.TABLES t,INFORMATION_SCHEMA.Columns c WHERE c.TABLE_NAME=t.TABLE_NAME AND t.`TABLE_SCHEMA`=','''',@dbName,'''');
END;
PREPARE stmt FROM @sqlstr;
EXECUTE stmt;
END//
DELIMITER ;
调用：
CALL findComment();
Face your past without regret. Handle your present with confidence.Prepare for future without fear. keep the faith and drop the fear...