Date: Thu, 16 Jun 2005 22:28:30 +0300
From: =?ISO-8859-1?Q?Veikko_M=E4kinen?= <veikko.makinen@ecom.fi>
Subject: How does the transaction buffer work?
To: pgsql-performance@postgresql.org
Message-id: <42B1D2DE.4020709@ecom.fi>
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Hey,

How does Postgres (8.0.x) buffer changes to a database within a 
transaction? I need to insert/update more than a thousand rows (mayde 
even more than 10000 rows, ~100 bytes/row) in a table but the changes 
must not be visible to other users/transactions before every row is 
updated. One way of doing this that I thought of was start a 
transaction, delete everything and then just dump new data in (copy 
perhaps). The old data would be usable to other transactions until I 
commit my insert. This would be the fastest way, but how much memory 
would this use? Will this cause performance issues on a heavily loaded 
server with too little memory even to begin with :)


-veikko