mysql / pgsql 使用sql语句查询数据库所有表注释已经表字段注释

mysql使用sql语句查询数据库所有表注释已经表字段注释(转载)

 

场景：

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();

转载自：http://blog.csdn.net/cicon/article/details/51577655

获取表名及注释：

select relname as tabname,cast(obj_description(relfilenode,'pg_class') as varchar) as comment from pg_class c 
where  relkind = 'r' and relname not like 'pg_%' and relname not like 'sql_%' order by relname

过滤掉分表：

加条件 and relchecks=0 即可

获取字段名、类型、注释、是否为空:
SELECT col_description(a.attrelid,a.attnum) as comment,format_type(a.atttypid,a.atttypmod) as type,a.attname as name, a.attnotnull as notnull   
FROM pg_class as c,pg_attribute as a where c.relname = '表名' and a.attrelid = c.oid and a.attnum>0