mysql中递归查询的实现

Posted 2020-10-19 chenhuan

1，执行如下代码即可实现递归查询：
delimiter // 
CREATE FUNCTION `getParLst`(rootId INT)
RETURNS varchar(1000) 

BEGIN
	DECLARE sTemp VARCHAR(1000);
    DECLARE sTempChd VARCHAR(1000);

    SET sTemp = ‘$‘;
    SET sTempChd =cast(rootId as CHAR);

    WHILE sTempChd is not null DO
    	SET sTemp = concat(sTemp,‘,‘,sTempChd);
        SELECT group_concat(id) INTO sTempChd FROM  treeNodes where FIND_IN_SET(pid,sTempChd)>0;
   	END WHILE;
    RETURN sTemp; 
END
//

2，如果有报错，请查询log_bin
例如：
SHOW VARIABLES LIKE ‘log_bin_trust_function_creators‘;
解决方法， 在mysql中执行如下语句：
SET GLOBAL log_bin_trust_function_creators=TRUE;
再查看
SHOW VARIABLES LIKE ‘log_bin_trust_function_creators‘;

OK解决！