Re: multi-column btree index for real values

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.
>
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