Re: plpgsql error handling bug

Tom Lane wrote:

 > Ivan-Sun1@mail.ru writes:
 >
 >>I found a bug in the behaviour of plpgsql error handling system
 >>while trying to handle foreign key violation exception.
 >
 >
 > This is not a bug in the exception system.
 >
 > The problem is that FK constraints are enforced by triggers that do not
 > fire until the end of the outer statement (that is, the SELECT that
 > calls the plpgsql function).  So by the time the constraint error is
 > raised, we have long since exited the exception structure.
 >
 > There has been some talk of changing trigger firing rules to make this
 > sort of thing behave more intuitively inside functions, but it hasn't
 > happened yet.
 >
 > Maybe we should think about doing something about this for 8.0?  It's a
 > larger behavioral change than I like to think about for post-beta, but
 > (a) the exception mechanism's usefulness is certainly going to be
 > severely limited if it can't catch FK errors; (b) 8.0 seems like a
 > more appropriate time to introduce backwards-incompatibilities than
 > future 8.x releases.

Considering also that if you fix the BUG #1231 then 8.0 have already some
backwards-incompatibilities so one more is mitigated by the other one.



Regards
Gaetano Mendola