id sname smoney sprovince
1 zhangsan 2098 A
2 lisi 3000 B
3 wangwu 6789 C
4 liumazi 4587 C
5 dongjiu 3298 B
6 shiga 4567 A

 

id:合同id  sname:姓名     smoney :业绩     sprovince:地区


第一道:显示出  业绩 大于同一地区平均值的 合同id  姓名 地区 业绩

第二道:把同一地区的  平均业绩 地区 插入到新表中 (新表只包含两个字段即:平均业绩 地区)


 create table T1
(
id int primary key not null,
sname varchar(20) unique not null,
smoney int not null,
sprovince varchar(20) not null
);
K, 0 rows affected (0.08 sec)

 insert into T1 (id,sname,smoney,sprovince)values
 (2,'bb',2025,'A');
K, 1 row affected (0.03 sec)

  insert into T1 (id,sname,smoney,sprovince)values
  (3,'cc',3025,'B');
K, 1 row affected (0.01 sec)

insert into T1 (id,sname,smoney,sprovince)values
(4,'dd',3455,'C');
K, 1 row affected (0.02 sec)

insert into T1 (id,sname,smoney,sprovince)values
(5,'ee',7025,'B');
K, 1 row affected (0.01 sec)

insert into T1 (id,sname,smoney,sprovince)values
(6,'ff',3905,'A');
K, 1 row affected (0.02 sec)

insert into T1 (id,sname,smoney,sprovince)values
(7,'gg',6354,'d');
K, 1 row affected (0.01 sec)

select * from T1;
+----+-------+--------+-----------+
| id | sname | smoney | sprovince |
+----+-------+--------+-----------+
|  1 | aa    |   1025 | A         |
|  2 | bb    |   2025 | A         |
|  3 | cc    |   3025 | B         |
|  4 | dd    |   3455 | C         |
|  5 | ee    |   7025 | B         |
|  6 | ff    |   3905 | A         |
|  7 | gg    |   6354 | d         |
+----+-------+--------+-----------+
in set (0.00 sec)

mysql> select a.* from T1 a where a.smoney>
(select avg(b.smoney) from T1 b where b.sprovince=a.sprovince);     答案一:
+----+-------+--------+-----------+
| id | sname | smoney | sprovince |
+----+-------+--------+-----------+
|  5 | ee    |   7025 | B         |
|  6 | ff    |   3905 | A         |
+----+-------+--------+-----------+

mysql> create table T2 as(
    -> select avg(smoney) avgmoney,sprovince from T1 group by sprovince);
Query OK, 4 rows affected, 1 warning (0.06 sec)
Records: 4  Duplicates: 0  Warnings: 1

mysql> select * from T2;
+-----------+-----------+
| avgmoney  | sprovince |
+-----------+-----------+
| 2318.3333 | A         |
| 5025.0000 | B         |
| 3455.0000 | C         |
| 6354.0000 | d         |
+-----------+-----------+
4 rows in set (0.00 sec)

 

 posted on 2009-03-21 13:55  将军  阅读(162)  评论(0编辑  收藏  举报