Date: Mon, 19 Sep 2011 20:53:42 -0400
From: Stephen Frost <sfrost@snowman.net>
To: Igor Chudov <ichudov@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Postgres INSERT performance and scalability
Message-ID: <20110920005342.GO12765@tamriel.snowman.net>
References: 
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Igor,

* Igor Chudov (ichudov@gmail.com) wrote:
> Would the time that it takes, differ a great deal, depending on whether the
> table has only 100,000 or 5,000,000 records?

Yes, because PostgreSQL is going to copy the data.  If you don't need or
want it to be copied, just use a view.  I've never heard of any
relational database implementing 'copy on write' type semantics, if
that's what you're asking about.  Databases, unlike applications with
code in memory that's constantly copied, are typically focused around
minimizing duplication of data (since it all has to end up on disk at
some point).  Not much point in having the overhead of COW for that kind
of environment, I wouldn't think.

	Thanks,

		Stephen

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