On Feb 19, 2007, at 18:04 , Alban Hertroys wrote:

Michael Glaesemann wrote:

On Feb 18, 2007, at 20:29 , Karsten Hilbert wrote:

What I don't understand, however, is exactly *why* date_trunc is not
immutable ?

I believe it's because the result of date_trunc depends on the time zone
setting for the session.

I understand the reasoning, but _under the conditions_ it is being used
by the OP it could have been immutable, right?

*Under the conditions* doesn't really make sense wrt immutable functions. Immutable means is immutable under all conditions.

Michael Glaesemann
grzm seespotcode net



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