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diff --git a/src/man/vacuum.l b/src/man/vacuum.l new file mode 100644 index 0000000000..297124cd61 --- /dev/null +++ b/src/man/vacuum.l @@ -0,0 +1,37 @@ +.\" This is -*-nroff-*- +.\" XXX standard disclaimer belongs here.... +.\" $Header: /cvsroot/pgsql/src/man/Attic/vacuum.l,v 1.1 1996/11/14 10:18:14 scrappy Exp $ +.TH VACUUM SQL 11/05/95 Postgres95 Postgres95 +.SH NAME +vacuum \(em vacuum a database +.SH SYNOPSIS +.nf +\fBvacuum [table]\fP +.fi +.SH DESCRIPTION +.BR Vacuum +is the Postgres vacuum cleaner. It opens every class in the database, +moves deleted records to the archive for archived relations, cleans +out records from aborted transactions, and updates statistics in the +system catalogs. The statistics maintained include the number of +tuples and number of pages stored in all classes. Running +.BR vacuum +periodically will increase Postgres's speed in processing user queries. +.PP +The open database is the one that is vacuumed. +.PP +We recommend that production databases be vacuumed nightly, in order +to keep statistics relatively current. The +.BR vacuum +query may be executed at any time, however. In particular, after +copying a large class into Postgres or deleting a large number of +records, it may be a good idea to issue a +.BR vacuum +query. This will update the system catalogs with the results of all +recent changes, and allow the Postgres query optimizer to make better +choices in planning user queries. +.PP +The purge(l) command can be used to control the archive retention +characteristics of a given table. +.SH "SEE ALSO" +purge(l). |