Thread: Migration from 8.0 to 7.4...
Hi, We've got a problem with postgres 8.0 (our own code is not ready yet for the new driver) but a production database is already on postgres 8.0 (too bad, we didn't tested it enough...). So we need to migrate back to postgres 7.4 and wait for a code upgrade. Is there a possible way to do this ? pg_dump output of 8.0 is not compatible with 7.4. But the output of "pg_dump -a" seems to be compatible. One solution would be to create tables with a 7.4 sql script. Then use pg_dump to get the data from the 8.0 database and fill them in the 7.4 database. And finally restore all functions and triggers from a 7.4 sql script. Before testing this way, I would like your advise to know if our solution has a chance to work, if there is a better way or anything... Thanks for any help -- Romain Vinot
Romain Vinot wrote: > Hi, > > We've got a problem with postgres 8.0 (our own code is not ready yet for > the new driver) but a production database is already on postgres 8.0 > (too bad, we didn't tested it enough...). What "new driver"? I wasn't aware of 8.0 not being able to work with drivers for 7.4 > So we need to migrate back to postgres 7.4 and wait for a code upgrade. > Is there a possible way to do this ? > > pg_dump output of 8.0 is not compatible with 7.4. But the output of > "pg_dump -a" seems to be compatible. > One solution would be to create tables with a 7.4 sql script. Then use > pg_dump to get the data from the 8.0 database and fill them in the 7.4 > database. And finally restore all functions and triggers from a 7.4 sql > script. I've had to do something similar. The easiest solution is to pg_dump --schema-only and run that through a perl script or similar to translate/correct any parts that are wrong. First though, verify that the downgrade is necessary. What specifically is the problem with 8.0? -- Richard Huxton Archonet Ltd
Romain, If you're using JDBC and the V3 protocol is hurting you (which was my case at one point), you can force the 8.0 driver to use the V2 protocol which does a lot of things differently. For a quick solution that could work until you fix your code to properly work with V3. Just shooting in the dark... Csaba. On Mon, 2005-10-24 at 10:02, Romain Vinot wrote: > Hi, > > We've got a problem with postgres 8.0 (our own code is not ready yet for > the new driver) but a production database is already on postgres 8.0 > (too bad, we didn't tested it enough...). > > So we need to migrate back to postgres 7.4 and wait for a code upgrade. > Is there a possible way to do this ? > > pg_dump output of 8.0 is not compatible with 7.4. But the output of > "pg_dump -a" seems to be compatible. > One solution would be to create tables with a 7.4 sql script. Then use > pg_dump to get the data from the 8.0 database and fill them in the 7.4 > database. And finally restore all functions and triggers from a 7.4 sql > script. > > Before testing this way, I would like your advise to know if our > solution has a chance to work, if there is a better way or anything... > > Thanks for any help
Good point. This is exactly my problem. I tried to switch to the V2 protocol with the 8.0 JDBC driver. But in this case, I have the same behavior than with the 7.4 driver working on the 8.0 database. To answer Richard Huxton : the problem of JDBC 7.4 driver with a 8.0 database is that autocommit/commit/rollback doesn't work anymore. And I have also this behavior with a 8.0 JDBC driver and V2 protocol. So, I'm back to my first point... Csaba Nagy a écrit : > Romain, > > If you're using JDBC and the V3 protocol is hurting you (which was my > case at one point), you can force the 8.0 driver to use the V2 protocol > which does a lot of things differently. For a quick solution that could > work until you fix your code to properly work with V3. > > Just shooting in the dark... > > Csaba. > > > On Mon, 2005-10-24 at 10:02, Romain Vinot wrote: > >>Hi, >> >>We've got a problem with postgres 8.0 (our own code is not ready yet for >>the new driver) but a production database is already on postgres 8.0 >>(too bad, we didn't tested it enough...). >> >>So we need to migrate back to postgres 7.4 and wait for a code upgrade. >>Is there a possible way to do this ? >> >>pg_dump output of 8.0 is not compatible with 7.4. But the output of >>"pg_dump -a" seems to be compatible. >>One solution would be to create tables with a 7.4 sql script. Then use >>pg_dump to get the data from the 8.0 database and fill them in the 7.4 >>database. And finally restore all functions and triggers from a 7.4 sql >>script. >> >>Before testing this way, I would like your advise to know if our >>solution has a chance to work, if there is a better way or anything... >> >>Thanks for any help > > > > ---------------------------(end of broadcast)--------------------------- > TIP 9: In versions below 8.0, the planner will ignore your desire to > choose an index scan if your joining column's datatypes do not > match > -- Romain Vinot - Ingénieur R&D Akio Software 43, rue de Dunkerque Tel : 01 53 20 63 80