MYSQL存储过程—执行动态SQL

MysqL存储过程中动态sql是使用字符串拼接sql语句，示例代码如下：

SET @selectsql = 'SELECT 	RECID, FCODE, FNAME, FdisCOUNT, FIMAGE, FVIDEO, FTYPE, FSORT, FISHOT FROM tsvbase ';
     IF(paintName<>'')THEN
        SET @selectsql =CONCAT(@selectsql,' where FNAME like ',"'%",paintName,"%'");
        IF(regionCode<>'')THEN
          SET @selectsql =CONCAT(@selectsql,' and FADMINMAPNM like', "'%",fgetRegionCode(regionCode),"%'");
        END IF;
     ELSE
     IF (regionCode<>'')THEN
        SET @selectsql =CONCAT(@selectsql,' where  FADMINMAPNM like', "'%",fgetRegionCode(regionCode),"%'");
        END IF;
     END IF;
       
     SET @selectsql =CONCAT(@selectsql,' order by FISHOT,FSORT  LIMIT ',CAST(m AS CHAR(10)),',',CAST(currPage AS CHAR(10)));
     SELECT @selectsql;
     
     PREPARE stmt FROM @selectsql;
     EXECUTE stmt ;
     DEALLOCATE PREPARE stmt;

注意：这里MysqL变量前缀带“@”，无需使用DECLARE声明。

执行步骤说明如下：

1. 字符串@selectsql赋值；
2. 根据条件使用concat拼接字符串；
3. 如果需要拼接orderby和分页字符串；
4. 使用PREPARE 完成sql预处理；
5. 执行sql
6. 释放资源