In this case, yes, because you have no ambiguities. Consider: select t1.a as a1 from t1 as ta, t1 as tb, t1 as tc where t1.a = 47 To which t1.a does t1.a refer?
In this case, yes, because you have no ambiguities. Consider: select t1.a as a1 from t1 as ta, t1 as tb, t1 as tc where t1.a = 47 To which t1.a does t1.a refer?