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使用一行從另一張表中選擇兩行

[英]Selecting two rows from another table using one row

表格1

[      id      -      title      -      content      -      class      ]
[      1       -        2        -         3         -        1        ]
[      1       -        2        -         3         -        2        ]

表2

[      id      -       data      -    permission     -      class      ]
[      a       -        b        -         c         -        1        ]
[      a       -        b        -         c         -        2        ]

在選擇所有table1時如何從table2中選擇列data

我的查詢是SELECT title, content FROM table1 WHERE class = 1

如何在此查詢中選擇列datapermission

假設關系基於類:

select table1.*,table2.data, table2.permission
from table1 
join table2 on table1.class = table2.class 
where table1.class = 1

您可以使用簡單的JOIN來做到這一點:

Select  T1.*, T2.Data, T2.Permission
From    Table1  T1
Join    Table2  T2  On  T1.Class = T2.Class
Where   T1.Class = 1
select t1.title, t1.content, t2.data from table1 t1 join table2 t2
on t1.class=t2.class

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