On Wednesday 12 Feb 2003 6:20 pm, you wrote:
> Hi,
> While testing select query with where condition for primary key
> and non primary key value, I got the following results
>
> Base database size Time taken to select one record using one
> query in milliseconds
That is not a correct measure. Postgresql has a latency. You select 1 record
it will return you in 200ms and 100 records in 201 ms. Does it make sense?
Try to benchmark for repeated and more number of rows as a part of query.
>
> With Primary key With Non primary Key
>
> 2000 15.8 15.7
> 10000 71.2 70.7
> 25000 174 173.5
> 100000 4319 3417
Do an explain analyze on those select query. Most probably postgresql is
scanning table sequentially. Which may be a good thing.
Further you have not specified what kind of tuning you have done to
postgresql. If you are running with defaults, well, you need to change them.
And don't read too much in a select query performance. There are lot many
things that affect the performance..
HTH
Shridhar