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SQL Server 2012正在检索表中2列的属性_Sql_Sql Server_Join_Sql Server 2012 - Fatal编程技术网

SQL Server 2012正在检索表中2列的属性

SQL Server 2012正在检索表中2列的属性,sql,sql-server,join,sql-server-2012,Sql,Sql Server,Join,Sql Server 2012,我有以下表格 高中生 朋友 ID1和ID2是高中生ID列中的ID(它们不相同)。如何为这两个列选择分数,这样我就有了: ID1 Grade ID2 Grade 你应该和高中生一起加入两次(每个ID栏) select t1.ID1 , t2.grade , t1.ID2 , t3.grade from Friends t1 join Highschooler t2 on t1.ID1 = t2.ID join Highschooler t3 o

我有以下表格

高中生

朋友

ID1和ID2是高中生ID列中的ID(它们不相同)。如何为这两个列选择分数,这样我就有了:

ID1   Grade    ID2   Grade

你应该和高中生一起加入两次(每个
ID
栏)

select t1.ID1
     , t2.grade
     , t1.ID2
     , t3.grade
from Friends t1 
join Highschooler t2 on t1.ID1 = t2.ID 
join Highschooler t3 on t1.ID2 = t3.ID