Re: Poor Delete performance

  Just for everyones information.  I removed the foreign key constraint
  that was on the table and was able to delete about 190K records in
  just over 5 seconds.  That is much more like it.  B^)

  This does appear to be an interesting *feature* with the way that
  constraints are handled.

--
Bill

On Mon, Mar 12, 2001 at 12:23:41PM -0600, Matthew wrote:
>     [snip]
>
> > This needs to be improved (if we can't get rid of the lookup completely,
> > maybe use a hash table instead of sequential scan?) but it's much too
> > late to consider fixing it for 7.1 :-(.
> >
> > Actually, though, it might be even stupider than that: it looks like
> > the queue should only be searched if the tuple being deleted was
> > inserted/modified earlier in the same transaction.  Assuming that that
> > doesn't apply to Bill's case, the only thing I can see that could be
> > causing O(N^2) behavior is the lappend() in deferredTriggerAddEvent.
> > That's simple enough that we *could* fix it for 7.1 ...
> >
>     This would be a welcome improvement.  I have for a long time noticed
> very slow delete performance when deleting a large number of records in one
> command.  I can give more detail if so desired.

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