mysql 递归查询

1、创建表：

DROP TABLE IF EXISTS `t_areainfo`;
CREATE TABLE `t_areainfo` (
 `id` int(11) NOT '' AUTO_INCREMENT,
 `level` int(11) DEFAULT '',
 `name` varchar(255) DEFAULT '',
 `parentId` int(11) DEFAULT '',
 `status` int(11) DEFAULT '',
 PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=65 DEFAULT CHARSET=utf8;

2、初始数据：

INSERT INTO `t_areainfo` VALUES ('', '', '中国', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '华北区', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '华南区', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '海淀区', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '丰台区', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '朝阳区', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区1', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区2', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区3', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区4', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区5', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区6', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区7', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区8', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区9', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区10', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区11', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区12', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区13', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区14', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区15', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区16', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区17', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区18', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区19', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区1', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区2', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区3', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区4', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区5', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区6', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区7', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区8', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区9', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区10', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区11', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区12', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区13', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区14', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区15', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区16', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区17', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区18', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', '北京XX区19', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省1', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省2', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省3', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省4', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省5', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省6', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省7', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省8', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省9', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省10', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省11', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省12', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省13', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省14', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省15', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省16', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省17', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省18', '', '');
INSERT INTO `t_areainfo` VALUES ('', '', 'xx省19', '', '');

3、向下递归：

利用find_in_set()函数和group_concat()函数实现递归查询：

DROP FUNCTION IF EXISTS queryChildrenAreaInfo;
CREATE FUNCTION queryChildrenAreaInfo(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;

4、调用方式：

SELECT queryChildrenAreaInfo(1);

查询id为"4"下面的所有节点

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

5、向上递归：

DROP FUNCTION IF EXISTS queryChildrenAreaInfo1;
CREATE FUNCTION queryChildrenAreaInfo1(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;

6、调用方式：

查询id为"7"的节点的所有上级节点：

SELECT * from t_areainfo where FIND_IN_SET(id,queryChildrenAreaInfo1(7));