From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ron Mayer <rm_pg@cheapcomplexdevices.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Multiple insert performance trick or performance misunderstanding?
Date: Sat, 24 Sep 2005 17:15:41 -0400
Message-ID: <23702.1127596541@sss.pgh.pa.us> (raw)
In-Reply-To: <dh4e88$25qe$1@news.hub.org>
References: <dh4e88$25qe$1@news.hub.org>
Ron Mayer <rm_pg@cheapcomplexdevices.com> writes:
> Is it expected that I'd be better off sending big
> concatenated strings like
> "insert into tbl (c1,c2) values (v1,v2);insert into tbl (c1,c2) values (v3,v4);..."
> instead of sending them one at a time?
It's certainly possible, if the network round trip from client to server
is slow. I do not think offhand that there is any material advantage
for the processing within the server (assuming you've wrapped the whole
thing into one transaction in both cases); if anything, the
concatenated-statement case is probably a bit worse inside the server
because it will transiently eat more memory. But network latency or
client-side per-command overhead could well cause the results you see.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, rm_pg@cheapcomplexdevices.com
Subject: Re: Multiple insert performance trick or performance misunderstanding?
In-Reply-To: <23702.1127596541@sss.pgh.pa.us>
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