Horton

Re: texteq/byteaeq: avoid detoast [REVIEW]

Itagaki Takahiro <itagaki.takahiro@gmail.com>

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From: Itagaki Takahiro <itagaki.takahiro@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Magnus Hagander <magnus@hagander.net>, KaiGai Kohei <kaigai@ak.jp.nec.com>, Andy Colson <andy@squeakycode.net>, Noah Misch <noah@leadboat.com>, pgsql-hackers@postgresql.org
Date: 2011-01-18T08:06:24Z
Lists: pgsql-hackers 
On Tue, Jan 18, 2011 at 05:39, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> I haven't looked at this patch, but it seems to me that it would be
> reasonable to conclude A != B if the va_extsize values in the toast
> pointers don't agree.

It's a very light-weight alternative of memcmp the byte data,
but there is still the same issue -- we might have different
compressed results if we use different algorithm for TOASTing.

So, it would be better to apply the present patch as-is.
We can improve the comparison logic over the patch in another
development cycle if possible.

-- 
Itagaki Takahiro