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Re: More then 1600 columns?

From: Dmitriy Igrishin <dmitigr(at)gmail(dot)com>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: More then 1600 columns?
Date: 2010-11-12 07:43:14
Message-ID: AANLkTi=wON2eeGEgtCJ6rBzxqZceQQoCKW-mmJU+VqSD@mail.gmail.com (view raw or flat)
Thread:
Lists: pgsql-general
Hey Peter,

Unfortunately, there is no indexes on arrays (only on expressions).
With hstore we can easily create GiST index for effective access.

2010/11/12 Peter Bex <Peter(dot)Bex(at)xs4all(dot)nl>

> On Fri, Nov 12, 2010 at 10:17:50AM +0300, Dmitriy Igrishin wrote:
> > Hey Mark,
> >
> > Yeah, I can't imagine an entity in a real project even with more than 100
> > columns. Its rare case.
> > But if you entities (rows/tuples) of some class (table) can contains
> > variable
> > set of columns (properties) you can look at hstore contrib module.
>
> What can also work extremely well is storing the data in an array.
> If you need to access the array based on more meaningful keys you could
> store key/index pairs in another table.
>
> This approach only works well if you have multiple arrays with the same
> layout.  You probably also need to build up your query dynamically if
> you need to access variable numbers of datapoints.
>
> Cheers,
> Peter
> --
> http://sjamaan.ath.cx
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-- 
// Dmitriy.

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