• mysql 递归查询


    1、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;

    2、初始数据:

    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 ('8', '0', '北京XX区1', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('9', '0', '北京XX区2', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('10', '0', '北京XX区3', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('11', '0', '北京XX区4', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('12', '0', '北京XX区5', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('13', '0', '北京XX区6', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('14', '0', '北京XX区7', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('15', '0', '北京XX区8', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('16', '0', '北京XX区9', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('17', '0', '北京XX区10', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('18', '0', '北京XX区11', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('19', '0', '北京XX区12', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('20', '0', '北京XX区13', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('21', '0', '北京XX区14', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('22', '0', '北京XX区15', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('23', '0', '北京XX区16', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('24', '0', '北京XX区17', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('25', '0', '北京XX区18', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('26', '0', '北京XX区19', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('27', '0', '北京XX区1', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('28', '0', '北京XX区2', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('29', '0', '北京XX区3', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('30', '0', '北京XX区4', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('31', '0', '北京XX区5', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('32', '0', '北京XX区6', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('33', '0', '北京XX区7', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('34', '0', '北京XX区8', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('35', '0', '北京XX区9', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('36', '0', '北京XX区10', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('37', '0', '北京XX区11', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('38', '0', '北京XX区12', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('39', '0', '北京XX区13', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('40', '0', '北京XX区14', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('41', '0', '北京XX区15', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('42', '0', '北京XX区16', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('43', '0', '北京XX区17', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('44', '0', '北京XX区18', '4', '0');
    INSERT INTO `t_areainfo` VALUES ('45', '0', '北京XX区19', '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');

    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));

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  • 原文地址:https://www.cnblogs.com/xiaoxi/p/5942805.html
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