mysql 动态sql的拼接以及执行分页

Posted 2021-02-10 竹根七

1：建立存储过程，标记参数

CREATE DEFINER=`root`@`localhost` PROCEDURE `pos_get_drugInList`(IN page integer,IN limitz integer,IN drugCodez VARCHAR(50),IN effectDatez VARCHAR(50),IN chainIdz VARCHAR(19))
BEGIN
DECLARE start integer;
set start = (page-1)*limitz;
set @sql = \'select * from dsos_vot_drugrecord where 1 = 1\';

    #获取药品信息（最多一千条）

    if drugCodez <> \'\' then 
      set @sql = CONCAT(@sql,\' and drugCode= \',drugCodez);
    end if;
    
    if effectDatez <> \'\' then 
      set @sql = CONCAT(@sql,\' and effectDate= \',\'\'\'\',effectDatez,\'\'\'\');end if;
    
    if chainIdz <> \'\' then 
      set @sql = CONCAT(@sql,\' and chainId= \',chainIdz);
    end if;
    set @sql = CONCAT(@sql,\' limit \',start,\', \',limitz);
    
--     PREPARE distSQL FROM @SQL ;
--     EXECUTE distSQL;
--     DEALLOCATE PREPARE distSQL ;    
select @sql;
END

2：先打印出sql字符串，判断是否是理想值

3：干掉注释，执行sql语句，看结果

CREATE DEFINER=`root`@`localhost` PROCEDURE `pos_get_drugInList`(IN page integer,IN limitz integer,IN drugCodez VARCHAR(50),IN effectDatez VARCHAR(50),IN chainIdz VARCHAR(19))
BEGINDECLARE start integer;
set start = (page-1)*limitz;
set @sql = \'select * from dsos_vot_drugrecord where 1 = 1\';

    #获取药品信息（最多一千条）

    if drugCodez <> \'\' then 
      set @sql = CONCAT(@sql,\' and drugCode= \',drugCodez);
    end if;
    
    if effectDatez <> \'\' then 
      set @sql = CONCAT(@sql,\' and effectDate= \',\'\'\'\',effectDatez,\'\'\'\');end if;
    
    if chainIdz <> \'\' then 
      set @sql = CONCAT(@sql,\' and chainId= \',chainIdz);
    end if;
    set @sql = CONCAT(@sql,\' limit \',start,\', \',limitz);
    
     PREPARE distSQL FROM @SQL ;
     EXECUTE distSQL;
     DEALLOCATE PREPARE distSQL ;    
#select @sql;
END

4：结果