Re: MD5 aggregate

From: Peter Eisentraut <peter_e(at)gmx(dot)net>
To: Dean Rasheed <dean(dot)a(dot)rasheed(at)gmail(dot)com>
Cc: PostgreSQL Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: MD5 aggregate
Date: 2013-06-13 21:46:48
Message-ID: 51BA3DC8.4070607@gmx.net
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On 6/13/13 5:35 AM, Dean Rasheed wrote:
> Attached is a patch implementing a new aggregate function md5_agg() to
> compute the aggregate MD5 sum across a number of rows.

That seems somewhat useful.

> In passing, I've tidied up and optimised the code in md5.c a bit ---
> specifically I've removed the malloc()/memcpy()/free() code that was
> unnecessarily making a copy of the entire input data just to pad it
> and append the bit count. This reduces the memory consumption of the
> existing md5() functions for large inputs, and gives a modest
> performance boost. As a result, the md5() function can no longer throw
> an out-of-memory error.

I think it would be better if you split this into two separate patches.

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