On Mon, 2009-11-30 at 10:50 -0800, Craig James wrote: > I have a million-row table (two text columns of ~25 characters each plus two integers, one of which is PK) that is replaced every week. Since I'm doing it on a live system, it's run inside a transaction. This is the only time the table is modified; all other access is read-only. > > I wanted to use "truncate table" for efficiency, to avoid vacuum and index bloat, etc. But when I do "truncate" inside a transaction, all clients are blocked from read until the entire transaction is complete. If I switch to "delete from ...", it's slower, but other clients can continue to use the old data until the transaction commits. > > The only work-around I've thought of is to create a brand new table, populate it and index it, then start a transaction that drops the old table and renames the new one. > > Any thoughts? Use partitioning so you can roll off data. http://www.postgresql.org/docs/8.3/interactive/ddl-partitioning.html Joshua D. Drake > > Thanks, > Craig > > -- PostgreSQL.org Major Contributor Command Prompt, Inc: http://www.commandprompt.com/ - 503.667.4564 Consulting, Training, Support, Custom Development, Engineering If the world pushes look it in the eye and GRR. Then push back harder. - Salamander -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
