T-SQL实例 列别名的用法举例

T-SQL实例，使用列的别名。
代码：

1> create table employee( --//创建测试用表
2>     ID          int,
3>     name        nvarchar (10),
4>     salary      int,
5>     start_date  datetime,
6>     city        nvarchar (10),
7>     region      char (1))
8> GO
1>
2> insert into employee (ID, name,    salary, start_date, city,       region)
3>               values (1,  'Jason', 40420,  '02/01/94', 'New York', 'W')
4> GO

(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (2,  'Robert',14420,  '01/02/95', 'Vancouver','N')
3> GO

(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (3,  'Celia', 24020,  '12/03/96', 'Toronto',  'W')
3> GO

(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (4,  'Linda', 40620,  '11/04/97', 'New York', 'N')
3> GO

(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (5,  'David', 80026,  '10/05/98', 'Vancouver','W')
3> GO

(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (6,  'James', 70060,  '09/06/99', 'Toronto',  'N')
3> GO

(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (7,  'Alison',90620,  '08/07/00', 'New York', 'W')
3> GO

(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (8,  'Chris', 26020,  '07/08/01', 'Vancouver','N')
3> GO

(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (9,  'Mary',  60020,  '06/09/02', 'Toronto',  'W')
3> GO

(1 rows affected)
1>
2> select * from employee
3> GO
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          1 Jason            40420 1994-02-01 00:00:00.000 New York   W
          2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
          4 Linda            40620 1997-11-04 00:00:00.000 New York   N
          5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
          6 James            70060 1999-09-06 00:00:00.000 Toronto    N
          7 Alison           90620 2000-08-07 00:00:00.000 New York   W
          8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
          9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected)
1>
2>
3> --Column AS Alias 列别名的用法
4> SELECT Name + ' ' + City AS CityName FROM Employee
5> GO
CityName
---------------------
Jason New York
Robert Vancouver
Celia Toronto
Linda New York
David Vancouver
James Toronto
Alison New York
Chris Vancouver
Mary Toronto

(9 rows affected)
--删除测试用表employee
1> drop table employee
2> GO