Re: multi-column btree index for real values

From: Martin Weinberg <weinberg(at)osprey(dot)astro(dot)umass(dot)edu>
To: Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
Cc: Martin Weinberg <weinberg(at)osprey(dot)astro(dot)umass(dot)edu>, Martijn van Oosterhout <kleptog(at)svana(dot)org>, "Martin D(dot) Weinberg" <weinberg(at)astro(dot)umass(dot)edu>, pgsql-general(at)postgresql(dot)org
Subject: Re: multi-column btree index for real values
Date: 2002-10-05 20:37:52
Message-ID: 200210052037.g95KbqvH028690@osprey.astro.umass.edu
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

Thanks Bruce. Some simple tests on a 10 million tuple data base shows
that r-tree works well for this. (It took me a while to realize
that I had to sort boxes of zero area rather than points).

However, it seems that the rtree index has a serious memory leak for
7.2.2. Is that known?

--Martin

Bruce Momjian wrote on Sat, 05 Oct 2002 14:30:47 EDT
>Martin Weinberg wrote:
>> Martijn,
>>
>> Thanks. So that implies that a multidimensional btree index is
>> useless for two columns of floats (one will probably always
>> be searching on the first index for a tree of large height).
>>
>> Let me restate my question as an example. Supose I have columns
>> of longitude and latitude. What is the best indexing strategy to
>> find all tuples with in a two dimensional bound of longitude and
>> latitude. E.g. with where clause
>>
>> lat between 21.49 and 37.41 and
>
>Oh, rtree. That is exactly the index type you want.
>
>--
> Bruce Momjian | http://candle.pha.pa.us
> pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
> + If your life is a hard drive, | 13 Roberts Road
> + Christ can be your backup. | Newtown Square, Pennsylvania 19073
>
>---------------------------(end of broadcast)---------------------------
>TIP 2: you can get off all lists at once with the unregister command
> (send "unregister YourEmailAddressHere" to majordomo(at)postgresql(dot)org)
>

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Bruce Momjian 2002-10-05 21:39:45 Re: multi-column btree index for real values
Previous Message Garo Hussenjian 2002-10-05 20:18:13 Re: Boolean output format