The Tsql IN Command ??

create table table1 (id int identity(1,1) not null, col1 varchar(50), col2 varchar(50))

create table table2 (id int identity(1,1) not null, col1 varchar(50))



insert into table1

(col1)

values('test')







insert into table2

(col1)

values('test')

--Correct query

select * From table1 where col1 in (Select col1 From table2)

--common type error and the query do not warn the user of the error at runtime???

select * From table1 where col1 in (Select col2 From table2) --<< surely this should generate a schema error?



now a select is not the end of the world, but have it been a delete, then the impact become very serious..

I had to restore my database in production because of such a delete