create table #t(a int,b int,c int)
goinsert into #t(a,b,c) values(1,1,1)
insert into #t(a,b,c) values(2,2,2)select * from #t--删除列c
alter table #t drop column c
go--添加计算列
alter table #t add c as a*b
goinsert into #t(a,b) values(3,3)
insert into #t(a,b) values(4,4)select * from #tdrop table #t
go
goinsert into #t(a,b,c) values(1,1,1)
insert into #t(a,b,c) values(2,2,2)select * from #t--删除列c
alter table #t drop column c
go--添加计算列
alter table #t add c as a*b
goinsert into #t(a,b) values(3,3)
insert into #t(a,b) values(4,4)select * from #tdrop table #t
go
解决方案 »
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