Re: Analyze tool?

Rob Sargent skrev 2010-10-01 15.43:
> Then to get all statements would one simply set log_min_duration to some
> arbitrarily small value?

From default postgresql.conf comments:

-1 is disabled, 0 logs all statements and their durations, > 0 logs only
statements running at least this number of milliseconds

Also see 18.7.2 in docs:
http://www.postgresql.org/docs/current/interactive/runtime-config-logging.html

Regards
/roppert

>
> On 10/01/2010 04:30 AM, Thom Brown wrote:
>> 2010/10/1 Bjørn T Johansen<btj(at)havleik(dot)no>:
>>> We are using both DB2 and PostgreSQL at work and DB2 has a nice tool, i5 Navigator, where one can enable logging of SQL statements and then it will
>>> recommed indexes that should/could be created to increase speed...
>>> Does there exist a similar tool for PostgreSQL?
>>
>> You can set log_min_duration_statement to log statements which take
>> over a certain amount of time, and then use pgFouine to read the log
>> files and identify the most frequently run queries, and the longest
>> queries.
>>
>> You can also use the auto_explain contrib module
>> (http://www.postgresql.org/docs/9.0/static/auto-explain.html) to log
>> the plans of queries which take too long. However, I don't think
>> pgFouine can use those outputs.. at least not yet.
>>
>> But to find out what indexes you'll need, getting used to reading
>> query plans will help as it will show you more than just where
>> sequentials scans are taking place. It will also show you what the
>> planner believes a query will cost compared to how much it actually
>> costs, which can provide insight into tables which require vacuuming,
>> indexes which might need clustering, or table stats which require
>> modifying to match you data.
>>
>> There might be a tool out there for PostgreSQL like you describe,
>> although I'm not personally aware of it.
>>
>