On Sun, Nov 23, 2008 at 3:28 PM, Stephen Frost <[EMAIL PROTECTED]> wrote:
> * Ciprian Dorin Craciun ([EMAIL PROTECTED]) wrote:
>> > Even better might be partitioning on the timestamp.  IF all access is
>> > in a certain timestamp range it's usually a big win, especially
>> > because he can move to a new table every hour / day / week or whatever
>> > and merge the old one into a big "old data" table.
>>
>>     Yes, If i would speed the inserts tremendously... I've tested it
>> and the insert speed is somewhere at 200k->100k.
>>
>>     But unfortunately the query speed is not good at all because most
>> queries are for a specific client (and sensor) in a given time
>> range...
>
> Have you set up your partitions correctly (eg, with appropriate CHECK
> constraints and with constraint_exclusion turned on)?  Also, you'd want
> to keep your indexes on the individual partitions, of course..  That
> should improve query time quite a bit since it should only be hitting
> the partitions where the data might be.
>
>        Stephen
>
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    Well, now that I've read the previous two emails better, I
understand what Scot and Stephen are talking about...

    So if I understood it correctly: I should build indexes only for
certain parts of the data (like previous full hour and so). But I see
a problem: wouldn't this lead to a lot of indices beeing created (24 /
hour, ~150 / week, ...)?

    Another question: wouldn't the index creation impact the insertion
and query speed during they are created?

    Either case I don't think this is a very easy to implement solution...

    Ciprian Craciun.

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