Re: Slow query with big tables

On Fri, Aug 26, 2016 at 9:11 PM, Jim Nasby <Jim(dot)Nasby(at)bluetreble(dot)com> wrote:

> On 8/26/16 3:26 PM, Mike Sofen wrote:
>
>> Is there way to keep query time constant as the database size grows.
>>
>
> No. More data == more time. Unless you find a way to break the laws of
> physics.
>

Straight hash-table indexes (which Postgres doesn't use) have O(1) access
time. The amount of data has no effect on the access time. Postgres uses
B-trees which have O(logN) performance. There is no "law of physics" that
says Postgres couldn't employ pure hash indexes.

Craig

> Should I use partitioning or partial indexes?
>>
>
> Neither technique is a magic bullet. I doubt either would help here.
> --
> Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
> Experts in Analytics, Data Architecture and PostgreSQL
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--
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Craig A. James
Chief Technology Officer
eMolecules, Inc.
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