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两种mysql递归tree查询效率-mysql递归tree PDF 下载


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时间:2020-09-18 13:19来源:http://www.java1234.com 作者:小锋  侵权举报
两种mysql递归tree查询效率-mysql递归tree PDF 下载
失效链接处理
两种mysql递归tree查询效率-mysql递归tree PDF 下载

 
本站整理下载:
 
相关截图:
 
主要内容:

--修改数据库设置,保证数据能够全部被拼接
SET GLOBAL group_concat_max_len = 102400;
SET SESSION group_concat_max_len = 102400;
或者
在my.ini文件中在max_connections=2000后边增加
group_concat_max_len=102400
检验语句
show variables like "group_concat_max_len";  
--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');
 
方式一:采用function获取所有子节点的id 1
--查询传入areaId及其以下所有子节点
DROP FUNCTION IF EXISTS queryChildrenAreaInfo;
CREATE FUNCTION `queryChildrenAreaInfo` (areaId INT)
RETURNS VARCHAR(15000)
BEGIN
DECLARE sTemp VARCHAR(15000);
DECLARE sTempChd VARCHAR(8000);
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;2


 

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