SqlSever基础 count 查询两个相关关联的表中的具有相同内容的行数

 1 --创建一个数据库
 2 create database helloworld1
 3 
 4 use master
 5 drop database helloworld1
 6 
 7 --用helloworld1这个数据库
 8 use helloworld1
 9 
10 --创建一个表格teacher
11 create table Teacher
12 (
13    Id int primary key identity(1,1),   
14    Name nvarchar(10),
15    Class nchar(2)
16 )
17 
18 create table Location
19 (
20    Class nchar(2),
21    location nvarchar(5)
22 )
23 
24 --看看 teacher这个表格有啥
25 select * from Teacher
26 select * from Location
27 
28 --向这个Teacher中插入这几行内容,这个内容我插入一遍后，简单修改，又插入一遍
29 insert into Teacher
30        values(‘文殊菩萨‘,‘佛家‘),
31              (‘普贤菩萨‘,‘佛家‘),
32              (‘观音菩萨‘,‘佛家‘),
33              (‘道德天尊‘,‘道家‘),
34              (‘灵宝天尊‘,‘道家‘),
35              (‘太白金星‘,‘道家‘),
36              (‘广寒仙子‘,‘道家‘)
37 
38 --向这个Location中插入这几行内容
39 insert into Location
40         values(‘佛家‘,‘印度‘),
41               (‘道家‘,‘中国‘),
42               (‘基督‘,‘西方‘),
43               (‘儒家‘,‘中国‘)
44 
45 --查看teacher表中有什么内容
46 select * from Teacher
47 
48 select * from
49 Teacher inner join Location on Teacher.Class=Location.Class
50 where Teacher.Class=‘道家‘
51 
52 select count(*) from
53 Teacher inner join Location on Teacher.Class=Location.Class
54 where Teacher.Class=‘道家‘