Re: Poor performance on very simple query ? - Mailing list pgsql-performance

Tobias Brox wrote:
> [Arnaud Lesauvage - Tue at 02:13:59PM +0200]
>> Tobias Brox wrote:
>> >Oh, the gid is not primary key.  I guess I should also apologize for
>> >adding noise here :-)
>>
>> Yes, it is a primary key, but I am the noise maker here ! ;-)
>
> Oh - it is.  How can you have a default value on a primary key?

Good question, but I am not the DB designer in that case.

 > Will it
> use the index if you do "analyze"?  Is there an index on the table at
> all, do you get it up if you ask for a description of the table (\d
> tablename)?

In this case (a simplified version of the real case), the pkey is the
only index. It is used if I only as for one row (WHERE gid=33).