Cast double precision to integer & check for overflow

I need to cast a double precision into an integer, and I want to check
that the value will actually fit (modulo rounding).

Coming from a C/Java background, this seems like something that should
be utterly trivial.  In my searching, however, I can't seem to find any
SQL equivalent of INT_MAX, Integer.MAX_VALUE, etc.

Do I have to hard-code this value?

Thanks!

(And yes, I do feel stupid having to ask this question here.)

--
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Ian Pilcher                                         arequipeno@gmail.com
Sometimes there's nothing left to do but crash and burn...or die trying.
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