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From: Jeff Janes <[email protected]>
To: Teodor Sigaev <[email protected]>
Cc: Rob Imig <[email protected]>
Cc: [email protected] <[email protected]>
Subject: Re: Performant queries on table with many boolean columns
Date: Thu, 21 Apr 2016 09:45:56 -0700
Message-ID: <CAMkU=1xXXANTYp7YLQjjzvgYCFQsr+y6iTphx1Q4y8iP7QpRjw@mail.gmail.com> (raw)
In-Reply-To: <[email protected]>
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On Wed, Apr 20, 2016 at 11:54 AM, Teodor Sigaev <[email protected]> wrote:
>>
>> The obvious thing seems to make a table with ~100 columns, with 1 column
>> for each boolean property. Though, what type of indexing strategy would
>> one use on that table? Doesn't make sense to do BTREE. Is there a better
>> way to structure it?
>>
> looks like a deal for contrib/bloom index in upcoming 9.6 release

Not without doing a custom compilation with an increased INDEX_MAX_KEYS:

ERROR:  cannot use more than 32 columns in an index

But even so, I'm skeptical this would do better than a full scan.  It
would be interesting to test that.

Cheers,

Jeff


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