On Tue, Jul 26, 2022 at 8:45 AM James Pang (chaolpan) <chaol...@cisco.com> wrote:
> Without step 3 , copy data take long time. Use wal_level=minimal can > help make COPY load data without logging ? > > I assume that you're most concerned with the total time of moving the data from the source database into the final table so you might get a big win by not moving the data twice and directly load the table through a Foregin Data Wrapper and avoid the csv export/import. Something like the oracle_fdw might help here: https://github.com/laurenz/oracle_fdw -----Original Message----- > From: Tom Lane <t...@sss.pgh.pa.us> > Sent: Tuesday, July 26, 2022 8:43 PM > To: James Pang (chaolpan) <chaol...@cisco.com> > Cc: Jim Mlodgenski <jimm...@gmail.com>; > pgsql-performance@lists.postgresql.org > Subject: Re: alter table xxx set unlogged take long time > > "James Pang (chaolpan)" <chaol...@cisco.com> writes: > > How to make it fast ? These are our steps about copy large data from > Oracle to Postgres > > 1. Create table in Postgres 2. Extract data from Oracle to CSV 3. > Alter table set xxx unlogged, 4. Run copy command into Postgres db 5. > Alter table set xxx logged 6. Create index … > > The easy answer is to skip steps 3 and 5. > > regards, tom lane >
