Re: GIST and TOAST - Mailing list pgsql-hackers

From Gregory Stark
Subject Re: GIST and TOAST
Date
Msg-id 87649ebbjs.fsf@stark.xeocode.com
Whole thread Raw
In response to Re: GIST and TOAST  (Andrew - Supernews <andrew+nonews@supernews.com>)
Responses Re: GIST and TOAST  (Gregory Stark <stark@enterprisedb.com>)
Re: GIST and TOAST  (Teodor Sigaev <teodor@sigaev.ru>)
List pgsql-hackers
"Andrew - Supernews" <andrew+nonews@supernews.com> writes:

> The places in the intarray code that you tried to "fix" in your patch at
> the start of this thread are not dealing with data that came from a tuple,
> but from data that came from a decompress method. It's expected that the
> decompress method does the detoasting.
>
> So I think you've mis-analyzed the problem. That's especially true since
> you are claiming that the existing code is already buggy when in fact no
> such bugs have been reported (and clearly intarray has been running with
> toasted array values for years).

I'm not claiming, I'm asking, because I can't tell. 

And it's not clear _int_gist.c has been running with toasted array values for
years because it's limited to arrays of 100 integers (or perhaps 200 integers,
there's a factor of 2 in the test). That's not enough to trigger toasting
unless there are other large columns in the same table.

I do know that with packed varlenas I get a crash in g_int_union among other
places. I can't tell where the datum came from originally and how it ended up
stored in packed format.

--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com


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