SQL AND & OR 运算符的使用方法
AND 和 OR 运算符
AND 和 OR 可在 WHERE 子语句中把两个或多个条件结合起来。
如果第一个条件和第二个条件都成立，则 AND 运算符显示一条记录。
如果第一个条件和第二个条件中只要有一个成立，则 OR 运算符显示一条记录。
and运行符实例
1> create table employee(
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> -- Use AND operator in where clause
3>
4> SELECT Name, ID
5> FROM Employee
6> WHERE Name > "Colin" AND Name < "Martin"
7> GO
Name ID
---------- -----------
Jason 1
Linda 4
David 5
James 6
OR 运算符实例
使用 OR 来显示所有姓为 "Carter" 或者名为 "Thomas" 的人：
SELECT * FROM Persons WHERE firstname='Thomas' OR lastname='Carter'
我们同一条sql查询语句中可以用到and or同时操作如下
实例
结合 AND 和 OR 运算符
我们也可以把 AND 和 OR 结合起来（使用圆括号来组成复杂的表达式）:
SELECT * FROM Persons WHERE (FirstName='Thomas' OR FirstName='William')
AND LastName='Carter'
补充：数据库,Mssql 
