Re: performance problem on big tables

I already finished migrating the system from oracle to postgresql. Right
now, I'm trying to improve its performance - Im bringing data from another
read only database that is updaded every minute. I cant push data from the
oracle side to the postgresql side because the oracle database is read only.

2017-08-21 17:35 GMT+03:00 Igor Neyman <ineyman(at)perceptron(dot)com>:

>
>
> *From:* pgsql-performance-owner(at)postgresql(dot)org [mailto:pgsql-performance-
> owner(at)postgresql(dot)org] *On Behalf Of *Mariel Cherkassky
> *Sent:* Monday, August 21, 2017 10:20 AM
> *To:* MichaelDBA <MichaelDBA(at)sqlexec(dot)com>
> *Cc:* pgsql-performance(at)postgresql(dot)org
> *Subject:* Re: [PERFORM] performance problem on big tables
>
>
>
> I had a system that consist from many objects(procedures,functions..) on
> an oracle database. We decided to integrate that system to postgresql. That
> system coppied alot of big tables from a different read only oracle
> database and preformed on it alot of queries to produce reports. The part
> of getting the data is part of some procedures, I cant change it so freely.
> I'm searching a way to improve the perfomance of the database because I'm
> sure that I didnt conifgure something well. Moreover, When I run complicted
> queries (joint between 4 big tables and filtering) it takes alot of time
> and I see that the server is cacheing all my ram memory.
>
>
>
>
>
> Probably your joins are done on Postgres side.
>
>
>
> m.b. instead of Postgres pulling data from Oracle, you should try pushing
> data from Oracle to Postgres using Oracle’s Heterogeneous Services and
> Postgres ODBC driver. In this case you do your joins and filtering on
> Oracles side and just push the result set to Postgres.
>
> That’s how I did migration from Oracle to Postgres.
>
>
>
> Regards,
>
> Igor Neyman
>