select Table1.* T1 where exists (select 1 from Table2 T2 where T1.pk_fld = T2.pk_fld and T2.fld2 = '123')>
>select Table1.* T1 where exists (select * from Table2 T2 where T1.pk_fld = T2.pk_fld and T2.fld2 = '123') >>
>select Table1.* T1 where T1.pk_fld in (select pk_fld from Table2 T2 where T1.pk_fld = T2.pk_fld and T2.fld2 = '123') >>