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Update manual pages for vacuum and create index for Vadim.
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.\" This is -*-nroff-*-
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.\" This is -*-nroff-*-
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.\" XXX standard disclaimer belongs here....
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.\" XXX standard disclaimer belongs here....
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.\" $Header: /cvsroot/pgsql/src/man/Attic/create_index.l,v 1.4 1997/01/13 17:22:25 momjian Exp $
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.\" $Header: /cvsroot/pgsql/src/man/Attic/create_index.l,v 1.5 1997/05/13 04:41:51 momjian Exp $
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.TH "CREATE INDEX" SQL 11/05/95 PostgreSQL PostgreSQL
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.TH "CREATE INDEX" SQL 11/05/95 PostgreSQL PostgreSQL
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.SH NAME
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.SH NAME
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create index \(em construct a secondary index
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create index \(em construct a secondary index
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@ -8,7 +8,7 @@ create index \(em construct a secondary index
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.nf
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.nf
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\fBcreate\fR [\fBunique\fR] \fBindex\fR index-name
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\fBcreate\fR [\fBunique\fR] \fBindex\fR index-name
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\fBon\fR classname [\fBusing\fR am-name]
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\fBon\fR classname [\fBusing\fR am-name]
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\fB(\fR attname [type_class\fB] )\fR
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\fB(\fR attname, ... [type_class\fB] )\fR
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\fBcreate\fR [\fBunique\fR] \fBindex\fR index-name
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\fBcreate\fR [\fBunique\fR] \fBindex\fR index-name
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\fBon\fR classname [\fBusing\fR am-name]
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\fBon\fR classname [\fBusing\fR am-name]
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@ -22,12 +22,12 @@ This command constructs an index called
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is the name of the access method which is used for the index.
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is the name of the access method which is used for the index.
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The default access method is btree.
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The default access method is btree.
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.PP
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.PP
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In the first syntax shown above, the key field for the index is
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In the first syntax shown above, the key fields for the index are
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specified as an attribute name and an associated
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specified as attribute names. It may also have an associated
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.IR "operator class" .
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.IR "operator class" .
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An operator class is used to specify the operators to be used for a
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An operator class is used to specify the operators to be used for a
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particular index. For example, a btree index on four-byte integers
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particular index.
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would use the
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For example, a btree index on four-byte integers would use the
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.IR int4_ops
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.IR int4_ops
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class; this operator class includes comparison functions for four-byte
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class; this operator class includes comparison functions for four-byte
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integers.
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integers.
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@ -40,7 +40,7 @@ result of a user-defined function
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applied to one or more attributes of a single class. These
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applied to one or more attributes of a single class. These
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.IR "functional indices"
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.IR "functional indices"
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are primarily useful in two situations. First, functional indices can
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are primarily useful in two situations. First, functional indices can
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be used to simulate multikey indices. That is, the user can define a
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be used to simulate multi-key indices. That is, the user can define a
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new base type (a simple combination of, say, \*(lqoid\*(rq and
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new base type (a simple combination of, say, \*(lqoid\*(rq and
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\*(lqint2\*(rq) and the associated functions and operators on this new
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\*(lqint2\*(rq) and the associated functions and operators on this new
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type such that the access method can use it. Once this has been done,
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type such that the access method can use it. Once this has been done,
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@ -260,6 +260,7 @@ and
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represent the use of
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represent the use of
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.IR "functional indices"
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.IR "functional indices"
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to simulate multi-key indices.
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to simulate multi-key indices.
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These are no longer needed now that multi-key indexes are supported.
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.PP
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.PP
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The Postgres query optimizer will consider using btree indices in a scan
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The Postgres query optimizer will consider using btree indices in a scan
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whenever an indexed attribute is involved in a comparison using one of:
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whenever an indexed attribute is involved in a comparison using one of:
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@ -1,12 +1,12 @@
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.\" This is -*-nroff-*-
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.\" This is -*-nroff-*-
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.\" XXX standard disclaimer belongs here....
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.\" XXX standard disclaimer belongs here....
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.\" $Header: /cvsroot/pgsql/src/man/Attic/vacuum.l,v 1.3 1997/01/13 03:45:33 momjian Exp $
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.\" $Header: /cvsroot/pgsql/src/man/Attic/vacuum.l,v 1.4 1997/05/13 04:41:54 momjian Exp $
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.TH VACUUM SQL 11/05/95 PostgreSQL PostgreSQL
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.TH VACUUM SQL 11/05/95 PostgreSQL PostgreSQL
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.SH NAME
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.SH NAME
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vacuum \(em vacuum a database
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vacuum \(em vacuum a database
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.SH SYNOPSIS
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.SH SYNOPSIS
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.nf
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.nf
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\fBvacuum [verbose] [\fPtable\fB]\fP
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\fBvacuum [verbose] [analyze] [\fPtable [(column,...)]\fB]\fP
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.fi
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.fi
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.SH DESCRIPTION
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.SH DESCRIPTION
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.BR Vacuum
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.BR Vacuum
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@ -20,6 +20,11 @@ periodically will increase Postgres's speed in processing user queries.
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.PP
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.PP
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\fBverbose\fP prints a detailed vacuum activity report for each table.
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\fBverbose\fP prints a detailed vacuum activity report for each table.
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.PP
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.PP
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\fBanalyze\fP also updates column statistics used by the optimizer to
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determine the most efficient way to execute a query.
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The statistics represent the disbursion of the data in each column.
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This information is valuable when several execution paths are possible.
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.PP
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The open database is the one that is vacuumed.
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The open database is the one that is vacuumed.
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.PP
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.PP
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We recommend that production databases be vacuumed nightly, in order
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We recommend that production databases be vacuumed nightly, in order
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