SQL server 2005 TSQL problem

Deal all\,

Table1			Table2
T1Col1	T1col2		T2Col1	T2col2
1	asdf		1	asdf
2	ghgh		2	ghgh
3	kkjk		3	kkjk
4	kkjk		4	ldflkl
5	jhjj		5	urws

Think that i have above 2 tables in SQL server 2005.

select * from table1 where T1Col1 in ( select T1Col1 from Table2)

should i except error for the above query ?

But SQL server 2005 is not giving any error , it is simple resulting all rows  from Table1


regards
ranganadh kodali