Lincoln Yeoh wrote: > At 06:32 PM 9/6/2007, Richard Huxton wrote: > >> Two other tips for bulk-updates like this: >> 1. Do as many columns in one go as you can >> 2. Only update rows that need updating >> >> When you've finished, a CLUSTER/VACUUM FULL can be useful too. > > How about: make sure you have enough free space because the table will > effectively double in size? Assuming it hasn't already been updated a few > times without vacuuming :). It is true for CLUSTER, but not for VACUUM FULL. -- Alvaro Herrera http://www.CommandPrompt.com/ PostgreSQL Replication, Consulting, Custom Development, 24x7 support ---------------------------(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
