数据库-内连接、左（外）连接、右（外）连接、全连接

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有学校和学生两张表，数据分别如下：

学校表

学生表

1.内连接语句以及结果：

select s.school_no,s.school_name,t.school_no,t.student_no from school s,student t where s.school_no=t.school_no;
select s.school_no,s.school_name,t.school_no,t.student_no from school s inner join student t on s.school_no=t.school_no;

2.左（外）连接语句以及结果：

select s.school_no,s.school_name,t.school_no,t.student_no from school s,student t where s.school_no=t.school_no(+);
select s.school_no,s.school_name,t.school_no,t.student_no from school s left /*outer*/ join student t on s.school_no=t.school_no;

3.右（外）连接语句以及结果：

select s.school_no,s.school_name,t.school_no,t.student_no from school s,student t where s.school_no(+)=t.school_no;
select s.school_no,s.school_name,t.school_no,t.student_no from school s right /*outer */ join student t on s.school_no=t.school_no;

4.全连接语句以及结果：

select s.school_no,s.school_name,t.school_no,t.student_no from school s full join student t on s.school_no=t.school_no;

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