[ADMIN] How to remove index from memory ?
Hello I am running a test to find the impact of corrupt indexes on queries. I corrupted the index file but observed that the queries continued to perform without issues. It was only on restart of the database that postgres realized that the indexes are corrupt and my queries started failing (with error like: ERROR: invalid page header in block 0 of relation base/16384/16399) My questions are: 1. How do I remove the indexes from memory ? I wish to stimulate the condition when indexes are no longer in database but the server has not restarted and see the effects of corrupt indexes. 2. Is there a more proactive and realtime way to detect corruption of indexes ? Thanks for any inputs.
Re: [ADMIN] replication from Oracle to PostgreSQL?
On 08/11/2011 08:09 PM, Craig Ringer wrote: On 11/08/2011 10:57 PM, CS DBA wrote: On Thu, 2011-08-11 at 08:41 -0600, CS DBA wrote: Anyone know of tools / options that will allow Oracle to PostgreSQL replication? or at least a real time feed or dblink? EnterpriseDB's Postgres Plus Advanced Server has a realtime replication solution bundled. Regards, That was the first thing I tried to push 'em towards... they shut it down cause it's not free (which is weird since they're not considering a real TCO, but they are the customer). Using Oracle ... and objecting to "not free"? That's why we're here - to help 'em migrate from Oracle to PostgreSQL, it seems some systems will need a longer Oracle life due to other constraints *boggle* agreed There are lots of ETL tools available, and there's always the roll-your-own queue-based trigger replication system option. Of course, both options would probably cost more than buying EDB's already built and tested version... interesting idea, any specific ETL tools you could recommend? -- Craig Ringer -- - Kevin Kempter - Constent State A PostgreSQL Professional Services Company www.consistentstate.com - -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
Re: [ADMIN] How to remove index from memory ?
A J wrote: > I am running a test to find the impact of corrupt indexes on > queries. I corrupted the index file but observed that the queries > continued to perform without issues. It was only on restart of the > database that postgres realized that the indexes are corrupt and > my queries started failing (with error like: ERROR: invalid page > header in block 0 of relation base/16384/16399) It sounds like you corrupted the disk image of the index, but the index was already cached in PostgreSQL shared memory, so the problem didn't appear. You restarted PostgreSQL, so it had to read from the OS cache or the actual disk, which caused it to see the bad pages. > 1. How do I remove the indexes from memory ? I wish to stimulate > the condition when indexes are no longer in database but the > server has not restarted and see the effects of corrupt indexes. You would need to create a workload which would need the shared memory of other purposes, so that the index pages eventually got evicted. Using a small shared_buffers setting would make this easier. > 2. Is there a more proactive and realtime way to detect corruption > of indexes ? I suppose that if PostgreSQL didn't cache data, but always read from disk it would notice sooner when something mangled the disk image, but performance would be horrible. Without reading the disk, you can't tell what's on the disk, so you can't tell if it is wrong. -Kevin -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
[ADMIN] pgpool replication mode
hi. excuse me for offtopic -- pgpool maillist is almost dead i want pgpool in replication mode to interrupt service in case of any backend failure. is it possible? -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
[ADMIN] lo_import/lo_export in other table
Hi all, How can I modify (or create other one) lo_import to save data in my table (not in pg_largeobject). Because I'm making an app that create a table with my fields and a bytea field, but .net doesn't read that field like lo_export. Any ideas? tks in advance,
Re: [ADMIN] replication from Oracle to PostgreSQL?
On 12/08/2011 10:40 PM, CS DBA wrote: There are lots of ETL tools available, and there's always the roll-your-own queue-based trigger replication system option. Of course, both options would probably cost more than buying EDB's already built and tested version... interesting idea, any specific ETL tools you could recommend? The main open source ones I hear about are Talend (http://uk.talend.com/index.php) and Pentaho (http://www.pentaho.com/). These are the only two I hear of people on this list using, but that doesn't mean others don't see use too. Others found in a quick search include CloverETL (http://www.cloveretl.com/) and Aptar (http://apatar.com/). I'm sure there are tons more, but who knows what they're like. -- Craig Ringer -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
