真实的国产乱ⅩXXX66竹夫人,五月香六月婷婷激情综合,亚洲日本VA一区二区三区,亚洲精品一区二区三区麻豆

SQL怎么實現(xiàn)分組limit

本篇內(nèi)容主要講解“SQL怎么實現(xiàn)分組limit”，感興趣的朋友不妨來看看。本文介紹的方法操作簡單快捷，實用性強。下面就讓小編來帶大家學(xué)習(xí)“SQL怎么實現(xiàn)分組limit”吧!

成都創(chuàng)新互聯(lián)專注于拱墅企業(yè)網(wǎng)站建設(shè),成都響應(yīng)式網(wǎng)站建設(shè)公司,商城網(wǎng)站建設(shè)。拱墅網(wǎng)站建設(shè)公司,為拱墅等地區(qū)提供建站服務(wù)。全流程定制網(wǎng)站開發(fā)，專業(yè)設(shè)計，全程項目跟蹤，成都創(chuàng)新互聯(lián)專業(yè)和態(tài)度為您提供的服務(wù)

MySQL> create table a (id int,fid int ,name varchar(10));
Query OK, 0 rows affected (0.10 sec)

mysql> insert into a value (1,1,'a');
Query OK, 1 row affected (0.04 sec)

mysql> insert into a value (2,1,'b');
Query OK, 1 row affected (0.01 sec)

mysql> insert into a value (3,1,'c');
Query OK, 1 row affected (0.01 sec)

mysql> insert into a value (4,2,'d');
Query OK, 1 row affected (0.02 sec)

mysql> insert into a value (5,2,'e');
Query OK, 1 row affected (0.01 sec)

mysql> insert into a value (6,2,'f');
Query OK, 1 row affected (0.00 sec)

mysql> select * from a
    -> ;
+------+------+------+
| id   | fid  | name |
+------+------+------+
|    1 |    1 | a    |
|    2 |    1 | b    |
|    3 |    1 | c    |
|    4 |    2 | d    |
|    5 |    2 | e    |
|    6 |    2 | f    |
+------+------+------+
6 rows in set (0.00 sec)

mysql> select * from a where 2>( select count(*) from a b where a.fid=b.fid and a.id+------+------+------+
| id | fid | name |
+------+------+------+
| 2 | 1 | b |
| 3 | 1 | c |
| 5 | 2 | e |
| 6 | 2 | f |
+------+------+------+
4 rows in set (0.00 sec)

mysql> select * from a where 2>( select count(*) from a b where a.fid=b.fid and a.id>b.id )order by fid ;
+------+------+------+
| id | fid | name |
+------+------+------+
| 1 | 1 | a |
| 2 | 1 | b |
| 4 | 2 | d |
| 5 | 2 | e |
+------+------+------+
4 rows in set (0.00 sec)