sql分组查询问题
情景一：
表中数据
name score
aaa 11
aaa 19
bbb 12
bbb 18
ccc 19
ddd 21
期望查询结果如下
name score
aaa 30
bbb 30
ccc 19
ddd 21
Sql代码
---检查表是否存在
if exists(select * from sysobjects where name='testSum')
drop table testSum
go
---创建表
create table testSum
(
tid int primary key identity(1,1),
tname varchar(30) null,
tscor int null
)
go
insert into testSum (tname,tscor)
select 'aaa',11
union all
select 'aaa',19
union all
select 'bbb',12
union all
select 'bbb',18
union all
select 'ccc',19
union all
select 'ddd',21
---查询语句
select tname ,sum(tscor) from testSum group by tname
---只查询tscor总和为30的
select tname ,sum(tscor) from testSum group by tname having sum(tscor)=30
---检查表是否存在
if exists(select * from sysobjects where name='testSum')
drop table testSum
go
---创建表
create table testSum
(
tid int primary key identity(1,1),
tname varchar(30) null,
tscor int null
)
go
insert into testSum (tname,tscor)
select 'aaa',11
union all
select 'aaa',19
union
相关文档：
--SQL 速查手册
/*******************************************/
SELECT
--用途：从指定表中取出指定列的数据
--语法：
SELECT column_name(s) from table_name
--主要字句可摘要为:
SELECT select_list [INTO new_table]
from table_source
[WHERE search_condition]
[GROUP BY group_by_expression]
[HAVING s ......
1.限制返回记录的行数（4-10行）
select rownum,c1 from t144 where rownum<10
minus
select rownum,c1 from t144 where rownum<5
2.批量插入
insert into tablename(select * from othertable)
或
insert into (column1,column2,,,,,,,)tablename(select column1,column2,,,,,,,from othertable)
3,分组函� ......
转自CSDN论坛：chaihuoniu
下列语句部分是Mssql语句，不可以在access中使用。
SQL分类：
DDL—数据定义语言(CREATE，ALTER，DROP，DECLARE)
DML—数据操纵语言(SELECT，DELETE，UPDATE，INSERT)
DCL—数据控制语言(GRANT，REVOKE，COMMIT，ROLLBACK)
首先,简要介绍基础语句：
1、说明：创建数� ......
insert into mysql.user
SELECT '%', 'admin', PASSWORD('admin'), Select_priv, Insert_priv, Update_priv,
Delete_priv, Create_priv, Drop_priv, Reload_priv,
Shutdown_priv, Process_priv, File_priv, Grant_priv, References_priv,
Index_priv, Alter_priv, Show_db_priv, Super_priv, ......
SQL> select * from dept where deptno=&tt;
Enter value for tt:20
DEPTNO DNAME LOC
------ -------------- -------------
10 ACCOUNTING NEW YORK
这样无论输入多少次tt的值，系统只建立一个执行计划，� ......
