Left join ,Right join ,inner join 的运行结果的区别

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Table1

   Name  City

   ----------

   张三  深圳

   李四  广州

Table2

   张六  深圳

   王五  顺德

---------------外联------------------------------------

select * from Table1 as a left join Table2 b on a.City=b.City

   Result:

   Name  City  Name  City

   --------------------

   张三  深圳  张六  深圳

   李四  广州  Null  Null

------------------外联---------------------------------

select * from Table1 as a right join Table2 b on a.City=b.City

   Null  Null  王五  顺德

-----------------外联-----------------------------------

select * from Table1 as a full  join Table2 b on a.City=b.City

----------------内联------------------------------------

select * from Table1 as a inner join Table2 b on a.City=b.City

(等于 select * from Table1 as a join Table2 b on a.City=b.City)

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