MySQL存储过程示例

-- 创建存储过程
CREATE DEFINER=`root`@`localhost` PROCEDURE `rename_file_name`()
begin
DECLARE flag INT;
DECLARE errfId BIGINT(20); -- e_relative_record_file id
DECLARE efrId BIGINT(20); -- e_file_record id
DECLARE renameFileName VARCHAR(200); -- 重新生成的图片文件名称
DECLARE target CURSOR FOR 
SELECT errf.id errfId,efr.id efrId,concat(substring_index(errf.file_name, '_', 1),'-',FLOOR(100+( RAND()*900)),'_cut0.jpg') renameFileName FROM e_relative_record_file errf INNER JOIN e_file_record efr ON errf.file_name = efr.file_name GROUP BY errf.file_name HAVING COUNT(errf.file_name)>1; -- 游标 查询重复的文件名称的数据
SET flag=0;
OPEN target;
REPEAT
     FETCH target into errfId,efrId,renameFileName; -- 变量赋值
     UPDATE e_relative_record_file SET file_name = renameFileName WHERE id= errfId;  -- 更新e_relative_record_file表重复的图片名称
     UPDATE e_file_record SET file_name = renameFileName WHERE id= efrId;     -- 更新e_file_record表重复的图片名称
UNTIL flag
END REPEAT;
CLOSE target;
end
-- 运行存储过程
call rename_file_name();
-- 删除存储过程
DROP PROCEDURE rename_file_name;