mysql递归查询

##创建表

DROP TABLE IF EXISTS `t_areainfo`;

CREATE TABLE `t_areainfo` (

 `id` int(11) NOT '0' AUTO_INCREMENT,

 `level` int(11) DEFAULT '0',

 `name` varchar(255) DEFAULT '0',

 `parentId` int(11) DEFAULT '0',

 `status` int(11) DEFAULT '0',

 PRIMARY KEY (`id`)

) ENGINE=InnoDB AUTO_INCREMENT=65 DEFAULT CHARSET=utf8;

 

##初始化数据

INSERT INTO `t_areainfo` VALUES ('1', '0', '中国', '0', '0');

INSERT INTO `t_areainfo` VALUES ('2', '0', '华北区', '1', '0');

INSERT INTO `t_areainfo` VALUES ('3', '0', '华南区', '1', '0');

INSERT INTO `t_areainfo` VALUES ('4', '0', '北京', '2', '0');

INSERT INTO `t_areainfo` VALUES ('5', '0', '海淀区', '4', '0');

INSERT INTO `t_areainfo` VALUES ('6', '0', '丰台区', '4', '0');

INSERT INTO `t_areainfo` VALUES ('7', '0', '朝阳区', '4', '0');

INSERT INTO `t_areainfo` VALUES ('46', '0', 'xx省1', '1', '0');

INSERT INTO `t_areainfo` VALUES ('47', '0', 'xx省2', '1', '0');

INSERT INTO `t_areainfo` VALUES ('48', '0', 'xx省3', '1', '0');

INSERT INTO `t_areainfo` VALUES ('49', '0', 'xx省4', '1', '0');

INSERT INTO `t_areainfo` VALUES ('50', '0', 'xx省5', '1', '0');

INSERT INTO `t_areainfo` VALUES ('51', '0', 'xx省6', '1', '0');

INSERT INTO `t_areainfo` VALUES ('52', '0', 'xx省7', '1', '0');

INSERT INTO `t_areainfo` VALUES ('53', '0', 'xx省8', '1', '0');

INSERT INTO `t_areainfo` VALUES ('54', '0', 'xx省9', '1', '0');

INSERT INTO `t_areainfo` VALUES ('55', '0', 'xx省10', '1', '0');

INSERT INTO `t_areainfo` VALUES ('56', '0', 'xx省11', '1', '0');

INSERT INTO `t_areainfo` VALUES ('57', '0', 'xx省12', '1', '0');

INSERT INTO `t_areainfo` VALUES ('58', '0', 'xx省13', '1', '0');

INSERT INTO `t_areainfo` VALUES ('59', '0', 'xx省14', '1', '0');

INSERT INTO `t_areainfo` VALUES ('60', '0', 'xx省15', '1', '0');

INSERT INTO `t_areainfo` VALUES ('61', '0', 'xx省16', '1', '0');

INSERT INTO `t_areainfo` VALUES ('62', '0', 'xx省17', '1', '0');

INSERT INTO `t_areainfo` VALUES ('63', '0', 'xx省18', '1', '0');

INSERT INTO `t_areainfo` VALUES ('64', '0', 'xx省19', '1', '0');

 

##向下递归查找

DROP FUNCTION IF EXISTS queryChildrenAreaInfoDown;

DELIMITER ;;

CREATE FUNCTION queryChildrenAreaInfoDown(areaId INT)

RETURNS VARCHAR(4000)

BEGIN

DECLARE sTemp VARCHAR(4000);

DECLARE sTempChd VARCHAR(4000);

 

SET sTemp='$';

SET sTempChd = CAST(areaId AS CHAR);

 

WHILE sTempChd IS NOT NULL DO

SET sTemp= CONCAT(sTemp,',',sTempChd);

SELECT GROUP_CONCAT(id) INTO sTempChd FROM t_areainfo WHERE FIND_IN_SET(parentId,sTempChd)>0;

END WHILE;

RETURN sTemp;

END;;

DELIMITER ;

 

##向上递归查找

DROP FUNCTION IF EXISTS queryChildrenAreaInfoUp;

DELIMITER ;;

CREATE FUNCTION queryChildrenAreaInfoUp(areaId INT)

RETURNS VARCHAR(4000)

BEGIN

DECLARE sTemp VARCHAR(4000);

DECLARE sTempChd VARCHAR(4000);

 

SET sTemp='$';

SET sTempChd = CAST(areaId AS CHAR);

SET sTemp = CONCAT(sTemp,',',sTempChd);

 

SELECT parentId INTO sTempChd FROM t_areainfo WHERE id = sTempChd;

WHILE sTempChd <> 0 DO

SET sTemp = CONCAT(sTemp,',',sTempChd);

SELECT parentId INTO sTempChd FROM t_areainfo WHERE id = sTempChd;

END WHILE;

RETURN sTemp;

END;;

DELIMITER ;

 

##使用验证

SELECT * FROM t_areainfo WHERE FIND_IN_SET(id,queryChildrenAreaInfoUp(4));

SELECT * FROM t_areainfo WHERE FIND_IN_SET(id,queryChildrenAreaInfoDown(1));