myql 查询树形表结果：说说、说说的评论、评论的回复

有三张表关联表：

用户的说说表（ixt_customer_note）

说说的评论表（ixt_customer_note_comment）

评论的回复表（ixt_customer_note_reply）

说说表保存的是用户发表的说说信息，评论表保存的是用户对说说发表的评论信息，回复表保存的是用户对评论及回复的回复

要求查询三张表返回结果为树形结构，如下：

发表说说:1003

发表说说:1002

发表评论:comment1002_1

发表评论:comment1002_2

发表回复:reply_1002_1

发表回复:reply_1002_2

发表评论:comment1002_3

发表说说:1001

发表评论:comment1001_1

发表评论:comment1001_2

发表说说:1000

发表评论:comment1000_1

发表回复:reply_1000_1

发表回复:reply_1000_2

1、设计三张表及插入相关数据

ixt_customer_note 表结构：

ixt_customer_note 表sql语句：

DROP TABLE IF EXISTS `ixt_customer_note`;

CREATE TABLE `ixt_customer_note` (

`id` varchar(50) NOT NULL COMMENT '主键UUID',

`customerId` varchar(50) NOT NULL COMMENT '用户id',

`content` varchar(500) NOT NULL COMMENT '说说内容',

`createUser` varchar(50) DEFAULT NULL COMMENT '创建人ID',

`createDate` datetime DEFAULT NULL COMMENT '创建时间',

`updateUser` varchar(50) DEFAULT NULL COMMENT '更新人ID',

`updateDate` datetime DEFAULT NULL COMMENT '更新时间',

`deleteFlag` bit(1) NOT NULL DEFAULT b'0' COMMENT '删除标识：0未删除，1删除',

PRIMARY KEY (`id`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO `ixt_customer_note` VALUES ('1000', 'user1', '1000', null, '2015-10-01 21:18:24', null, null, '');

INSERT INTO `ixt_customer_note` VALUES ('1001', 'user1', '1001', null, '2015-10-06 21:18:19', null, null, '');

INSERT INTO `ixt_customer_note` VALUES ('1002', 'user1', '1002', null, '2015-10-14 22:05:04', null, null, '');

INSERT INTO `ixt_customer_note` VALUES ('1003', 'user1', '1003', null, '2015-10-15 21:18:12', null, null, '');

ixt_customer_note_comment 表结构：

ixt_customer_note_comment 表sql语句：

DROP TABLE IF EXISTS `ixt_customer_note_comment`;

CREATE TABLE `ixt_customer_note_comment` (

`id` varchar(50) NOT NULL COMMENT '主键UUID',

`customerId` varchar(50) NOT NULL COMMENT '评论用户ID',

`dataId` varchar(50) NOT NULL COMMENT '被评论的说说ID',

`content` varchar(1000) NOT NULL COMMENT '评论内容',

`createUser` varchar(50) DEFAULT NULL COMMENT '创建人ID',

`createDate` datetime DEFAULT NULL COMMENT '更新人ID',

`updateUser` varchar(50) DEFAULT NULL COMMENT '更新时间',

`updateDate` datetime DEFAULT NULL COMMENT '更新时间',

`deleteFlag` bit(1) NOT NULL DEFAULT b'0' COMMENT '删除标识：0未删除，1删除',

PRIMARY KEY (`id`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO `ixt_customer_note_comment` VALUES ('1111', 'a1', '1001',
'comment1001_1', null, '2015-10-12 21:21:22', null, null, '');

INSERT INTO `ixt_customer_note_comment` VALUES ('1212', 'a2', '1001',
'comment1001_2', null, '2015-10-12 22:21:11', null, null, '');

INSERT INTO `ixt_customer_note_comment` VALUES ('2121', 'b3', '1002',
'comment1002_3', null, '2015-10-15 21:22:48', null, null, '');

INSERT INTO `ixt_customer_note_comment` VALUES ('321', 'b1', '1002',
'comment1002_1', null, '2015-10-14 21:21:59', null, null, '');

INSERT INTO `ixt_customer_note_comment` VALUES ('3221', 'c1', '1000',
'comment1000_1', null, '2015-10-02 21:23:19', null, null, '');

INSERT INTO `ixt_customer_note_comment` VALUES ('421', 'b2', '1002',
'comment1002_2', null, '2015-10-15 21:22:25', null, null, '');

ixt_customer_note_reply 表结构：

ixt_customer_note_reply 表sql语句：

DROP TABLE IF EXISTS `ixt_customer_note_reply`;

CREATE TABLE `ixt_customer_note_reply` (

`id` varchar(50) NOT NULL COMMENT '主键UUID',

`customerId` varchar(50) NOT NULL COMMENT '回复用户id',

`commentDataId` varchar(50) DEFAULT NULL COMMENT '被回复的评论ID',

`parentReplyDataId` varchar(50) DEFAULT NULL COMMENT '被回复的回复的id',

`content` varchar(1000) NOT NULL COMMENT '回复内容',

`createUser` varchar(50) DEFAULT NULL COMMENT '创建人ID',

`createDate` datetime DEFAULT NULL COMMENT '更新人ID',

`updateUser` varchar(50) DEFAULT NULL COMMENT '更新时间',

`updateDate` datetime DEFAULT NULL COMMENT '更新时间',

`deleteFlag` bit(1) NOT NULL DEFAULT b'0' COMMENT '删除标识：0未删除，1删除',

PRIMARY KEY (`id`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO `ixt_customer_note_reply` VALUES ('1212', 'v1', '3221',
null, 'reply_1000_1', null, '2015-10-12 21:28:44', null, null, '');

INSERT INTO `ixt_customer_note_reply` VALUES ('3121', 'v2', '3221',
'1212', 'reply_1000_2', null, '2015-10-13 21:28:49', null, null, '');

INSERT INTO `ixt_customer_note_reply` VALUES ('431', 'v3', '421',
null, 'reply_1002_1', null, '2015-10-14 21:28:54', null, null, '');

INSERT INTO `ixt_customer_note_reply` VALUES ('5231', 'v4', '421',
'431', 'reply_1002_2', null, '2015-10-15 21:28:57', null, null, '');

2、分别查出三张表的数据：

2.1、查询用户说说表倒序显示

select createDate, id as dataId, customerId, concat('发表说说:',content) as content from ixt_customer_note order by createDate desc;

2.2、查询说说的评论正序显示

select nc.createDate, nc.dataId, nc.customerId,
concat('发表评论:',nc.content) as content from ixt_customer_note_comment nc
left join ixt_customer_note n on nc.dataId=n.id order by n.createDate
desc, nc.createDate asc;

2.3、查询说说的评论的回复正序显示

select nr.createDate, nc.dataId, nr.customerId,
concat('发表回复:',nr.content) as content from ixt_customer_note_reply nr
left join ixt_customer_note_comment nc on nr.commentDataId=nc.id left
join ixt_customer_note n on nc.dataId=n.id order by n.createDate desc,
nc.createDate asc, nr.createDate asc;

3、有了这三张表数据后，如何将他们显示为一张表，最终得到树形结构？

如果想要得到树形展示，可以考虑能否将三张表返回的结果合并为一张表，因为他们的结果合并在一起后正是我们需要的所有数据，只不过最终展示的效果要调整一下。

好的，先考虑合并用户说说及说说的评论，并按树形结构展示，这时我们应该使用 union关键字，求并集。观察一下，合并之后的结果集，应该先根据说说的发表时间倒序，再根据说说的评论的发表时间正序，所以写sql执行一下：

大致的语句为：select * from(说说的结果集 union 评论的结果集) as T order by 说说.createDate desc, 评论.createDate asc;

select * from((select createDate as createDate1, "" as createDate2,
id as dataId, customerId, concat('发表说说:',content) as content from
ixt_customer_note order by createDate desc) union (select n.createDate
as createDate1, nc.createDate as createDate2, nc.dataId, nc.customerId,
concat('    发表评论:',nc.content) as content from ixt_customer_note_comment
nc left join ixt_customer_note n on nc.dataId=n.id  order by
n.createDate desc, nc.createDate asc)) as T order by createDate1 desc,
createDate2 asc;

4、上面合并结果集是我们想要的结果，好的，再来合并回复结果集。合并之后的结果集应该按说说的发表时间倒序，再按评论的发表时间正序，再按回复的发表时间正序。为了区分出每条记录是哪张表的，我们在结果集中添加一个字段type，表示记录的类型：t1是说说，t2是评论，t3是回复。

sql语句：select * from(说说的结果集 union 评论的结果集 union 回复的结果集) as T order
by 说说.createDate desc, 评论.createDate asc, 回复.createDate asc;

select * from((select createDate as createDate1, "" as createDate2,
"" as createDate3, "t1" as type, id as dataId, customerId,
concat('发表说说:',content) as content from ixt_customer_note order by
createDate desc) union (select n.createDate as createDate1,
nc.createDate as createDate2, "" as createDate3, "t2" as type,
nc.dataId, nc.customerId, concat('    发表评论:',nc.content) as content from
ixt_customer_note_comment nc left join ixt_customer_note n
on nc.dataId=n.id  order by n.createDate desc, nc.createDate asc) union
(select n.createDate as createDate1, nc.createDate as createDate2,
nr.createDate as createDate3, "t3" as type, nc.dataId, nr.customerId,
concat('        发表回复:',nr.content) as content from
ixt_customer_note_reply nr left join ixt_customer_note_comment nc on
nr.commentDataId=nc.id left join ixt_customer_note n on nc.dataId=n.id
order by n.createDate desc, nc.createDate asc, nr.createDate asc)) as T
order by createDate1 desc, createDate2 asc, createDate3 asc;

5、上面结果集是我们想要的，不过createDate最终应该只有一个，可以继续改进，将createDate合并为一列，说说显示createDate1，评论显示createDate2，回复显示createDate3。

改进后的语句如下：

select
if(T.type='t1',T.createDate1,(if(T.type='t2',T.createDate2,T.createDate3)))
as createDate, T.type, T.dataId, T.customerId, T.content from((select
createDate as createDate1, "" as createDate2, "" as createDate3, "t1"
as type,customerId, id as dataId, concat('发表说说:',content) as content
from ixt_customer_note order by createDate desc) union (select
n.createDate as createDate1, nc.createDate as createDate2, "" as
createDate3, "t2" as type, nc.customerId, nc.dataId, concat('  
 发表评论:',nc.content) as content from ixt_customer_note_comment nc left
join ixt_customer_note n on nc.dataId=n.id  order by n.createDate desc,
nc.createDate asc) union (select n.createDate as createDate1,
nc.createDate as createDate2, nr.createDate as createDate3, "t3" as
type, nr.customerId, nc.dataId, concat('        发表回复:',nr.content) as
content from ixt_customer_note_reply nr left join
ixt_customer_note_comment nc on nr.commentDataId=nc.id left join
ixt_customer_note n on nc.dataId=n.id order by n.createDate desc,
nc.createDate asc, nr.createDate asc)) as T order by createDate1 desc,
createDate2 asc, createDate3 asc;

myql 查询树形表结果：说说、说说的述评、评论的回复的更多相关文章

  1. myql查询创建表语句SHOW CREATE TABLE table_name

    技术背景:刚开始学习MySQL时候,有时偷懒,会用SHOW CREATE TABLE 表名\G来复制表创建语句,可是当运行的时候总会因为"表名和列名上有单引号",提示语法错误不能运 ...

  2. oracle 树形表结构查询 排序

    oracle 树形表结构排序 select * from Table start with parentid is null connect by prior id=parentid order SI ...

  3. SQL Server 树形表非循环递归查询

    很多人可能想要查询整个树形表关联的内容都会通过循环递归来查...事实上在微软在SQL2005或以上版本就能用别的语法进行查询,下面是示例.   --通过子节点查询父节点WITH  TREE AS(  ...

  4. sql查询指定表外键约束

    //////////////////查询指定表外键约束select a.name as 约束名, object_name(b.parent_object_id) as 外键表, d.name as 外 ...

  5. SQL查询每个表的字段数量

    --SQL查询每个表的字段数量select b.[name], count(*) As AllCount,ISNULL(ISNULL(sum(case when isnullable=0 then 1 ...

  6. SQL server 查询某个表在哪些存储过程（SP）中使用到

    1.查询某个表被哪些存储过程(以下简称 SP)使用到 : select distinct object_name(id) from syscomments where id in (select ob ...

  7. SQL 查询所有表名、字段名、类型、长度、存储过程、视图

    -- 获得存储过程创建语句 select o.xtype,o.name,cm.text from syscomments cm inner join sysobjects o on o.id=cm.i ...

  8. 【转】oracle查询用户表,函数,储存过程,

    ◆Oracle查询用户表空间:select * from user_all_tables ◆Oracle查询所有函数和储存过程:select * from user_source ◆Oracle查询所 ...

  9. SQL语句查询某表的所有字段及数据类型

    SQL语句查询某表的所有字段及数据类型 SELECT name AS column_name , TYPE_NAME(system_type_id) AS column_type , max_leng ...

随机推荐

  1. 几个MQTT的知识点

    开始正文前需要感谢一下网友“小龙”和emqtt.io群里的网友们的帮助,本人刚刚开始使用MQTT有很多不懂的地方,在emqtt.io群里询问解决方法的时候,“小龙”给我详细的讲解了一些MQTT的知识点 ...

  2. vi学习总结

    1.模式 命令行模式:光标的移动.内容删除移动复制操作 插入模式:文字输入,即编辑状态 底行模式:文件保存或退出vi,设置编辑环境 2.基本操作 vi myfile,输入vi 文件名,,则进入vi. ...

  3. Android——WebView

    WebView用途 通过Intent调用系统浏览器: 引言: Uri uri = Uri.parse(url);//url为你要链接的地址 Intent intent = new Intent(Int ...

  4. cavans 详解

    http://blog.csdn.net/clh604/article/details/8536059

  5. 传统瀑布式&敏捷开发

    ---传统瀑布式 瀑布模型式是最典型的预见性的方法,严格遵循预先计划的需求.分析.设计.编码.测试的步骤顺序进行. 步骤成果作为衡量进度的方法,例如需求规格,设计文档,测试计划和代码审阅等等. 瀑布式 ...

  6. C#客户端的异步操作

    上篇博客[用Asp.net写自己的服务框架] 我讲述了如何实现自己的服务框架,但我想很多人应该用过WebService这类服务框架,相比起来,似乎还缺少什么东西, 是的,我也感觉到了.比如:我可以很容 ...

  7. dynamic 用法

    private static string GetNameValue(object value) { dynamic obj = value; try { return obj.Name; } cat ...

  8. spring data jpa 调用存储过程

    网上这方面的例子不是很多,研究了一下,列出几个调用的方法. 假如我们有一个mysql的存储过程 CREATE DEFINER=`root`@`localhost` PROCEDURE `plus1in ...

  9. hibernate学习一（hibernate简介与准备）

    一.hibernate简介 Hibernate是一个开放源代码的对象-关系映射(Object/Relational Mapping 即 ORM)框架,它对JDBC进行了非常轻量级的对象封装,它将POJ ...

  10. c语言第一章第一节 认识变量

    声明:本人大一新生,闲着无聊..写写c语言教程..菜鸟一枚..大神勿喷!!! 接下来我们都用dev来进行编译..vc++太古老了,没提示功能,不好上手,并且老是出毛病..vs太大了,编个c不至于,运行 ...