Re: Increasing pattern index query speed

Andrus wrote:
> Richard,
>
>>> Results are provided in bottom of the message to which you replied.
>>
>> No - the explains there were contrasting a date test BETWEEN versus =.
>
> I changed rid.toode statitics target to 100:
>
> ALTER TABLE firma2.rid ALTER COLUMN toode SET STATISTICS 100;
> analyze firma2.rid;
>
> Analyze takes 3 seconds and testcase rans fast.
> I'm planning to monitor results by looking log file for queries which
> take longer than 10 seconds.

Sensible. I don't know if 10 seconds is the right value for your
database, but there will be a point that filters out most of your
traffic but still gives enough to find problems.

> Do you still need results ?
> If yes, which query and how many times should I run?

If changing the statistics seems to help, you're not going to want to go
back just to repeat tests.

>> Ah, I think I understand. The test case was *missing* this clause.
>
> I added this clause to testcase. Also added char(70) colums containing
> padding characters to all three tables. Cannot still reproduce this issue
> in testcase in fast devel 8.3 notebook.
> In testcase order_products contains product_id values in a very regular
> order, maybe this affects the results. No idea how to use random() to
> generate random
> products for every order.

Ideally you don't even want random products. You want a distribution of
products that matches the same "shape" as you have in your production
database.

--
Richard Huxton
Archonet Ltd