Tom Lane wrote: > Dave Smith <[EMAIL PROTECTED]> writes: > > My point was that it was inconstant behavour. What exactly are you > > comparing with int2? To me the case without the cast should should throw > > the same error as the statement with the cast. > > > select * from test where f=1981928928921; > > I contend not. The above is perfectly well defined. It will always > return false if f is int2, but that does not mean it should throw an > error instead. In any standard programming language, you'd resolve > the operator by up-converting f to the type of the constant, not by > trying to down-convert the wider value. PG happens to have > implementation reasons to wish to use the variable's datatype instead > of the constant's, but that doesn't excuse us from obeying the ordinary > laws of arithmetic.
Hmm...but what if the cast were to return NULL in the event that the cast fails or cannot be done? Would that even be reasonable? I don't know what the standard says about this so my suggestion may be unreasonable (and it may break a lot of things as well). In a way, this would be consistent with the meaning of NULL: "no value", and would also yield the desired effect in the example select (no matches). Of course, I could always be off my rocker here. :-) -- Kevin Brown [EMAIL PROTECTED] ---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match