Re: Slow query in JDBC

Good catch Jeff.

as for which version. We always recommend the latest version. 42.1.4

Dave Cramer

davec(at)postgresintl(dot)com
www.postgresintl.com

On 29 September 2017 at 06:44, Subramaniam C <subramaniam31784(at)gmail(dot)com>
wrote:

> Yes you are right the timestamp which the application was providing was in
> seconds whereas the query which was using index had a timestamp in
> milliseconds. So the query was taking time in application.
>
> On Fri, Sep 29, 2017 at 12:19 PM, Jeff Janes <jeff(dot)janes(at)gmail(dot)com> wrote:
>
>> On Thu, Sep 28, 2017 at 2:59 AM, Subramaniam C <
>> subramaniam31784(at)gmail(dot)com> wrote:
>>
>>> First output show the output when the query is executed from sql command
>>> line. The second output show when it is executed from the application. AS
>>> per the output it is clear that the when the query is executed through JDBC
>>> its not using the index (health_index) instead its doing sequence scan.
>>> Please let us know how this issue can be resolved from JDBC?
>>>
>>> 1.)
>>>
>>>
>>> * -> Index Only Scan
>>> using health_index on health_timeseries_table (cost=0.56..421644.56
>>> rows=1558800 width=24)*
>>>
>>> * Index Cond: (("timestamp" >=
>>> '1505989186834'::bigint) AND ("timestamp" <= '1505990086834'::bigint))*
>>>
>>>
>>
>>> 2.)
>>>
>>>
>>> -> Seq Scan on
>>> health_timeseries_table (cost=0.00..267171.00 rows=1005634 width=24)
>>>
>>> Filter: (("timestamp" >=
>>> '1505989500000'::bigint) AND ("timestamp" <= '1505990400000'::bigint))
>>>
>>
>>
>> Those are different queries, so it is not terribly surprising it might
>> choose a different plan.
>>
>> For this type of comparison, you need to compare identical queries,
>> including parameter.
>>
>> Cheers,
>>
>> Jeff
>>
>
>