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Update manual pages for vacuum and create index for Vadim.

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Bruce Momjian 1997-05-13 04:41:54 +00:00
parent 1e790e207f
commit f22f57ca35
2 changed files with 15 additions and 9 deletions
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15
src/man/create_index.l
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@ -1,6 +1,6 @@
.\" This is -*-nroff-*-
.\" XXX standard disclaimer belongs here....
.\" $Header: /cvsroot/pgsql/src/man/Attic/create_index.l,v 1.4 1997/01/13 17:22:25 momjian Exp $
.\" $Header: /cvsroot/pgsql/src/man/Attic/create_index.l,v 1.5 1997/05/13 04:41:51 momjian Exp $
.TH "CREATE INDEX" SQL 11/05/95 PostgreSQL PostgreSQL
.SH NAME
create index \(em construct a secondary index
@ -8,7 +8,7 @@ create index \(em construct a secondary index
.nf
\fBcreate\fR [\fBunique\fR] \fBindex\fR index-name
\fBon\fR classname [\fBusing\fR am-name]
\fB(\fR attname [type_class\fB] )\fR
\fB(\fR attname, ... [type_class\fB] )\fR
\fBcreate\fR [\fBunique\fR] \fBindex\fR index-name
\fBon\fR classname [\fBusing\fR am-name]
@ -22,12 +22,12 @@ This command constructs an index called
is the name of the access method which is used for the index.
The default access method is btree.
.PP
In the first syntax shown above, the key field for the index is
specified as an attribute name and an associated
In the first syntax shown above, the key fields for the index are
specified as attribute names. It may also have an associated
.IR "operator class" .
An operator class is used to specify the operators to be used for a
particular index. For example, a btree index on four-byte integers
would use the
particular index.
For example, a btree index on four-byte integers would use the
.IR int4_ops
class; this operator class includes comparison functions for four-byte
integers.
@ -40,7 +40,7 @@ result of a user-defined function
applied to one or more attributes of a single class. These
.IR "functional indices"
are primarily useful in two situations. First, functional indices can
be used to simulate multikey indices. That is, the user can define a
be used to simulate multi-key indices. That is, the user can define a
new base type (a simple combination of, say, \*(lqoid\*(rq and
\*(lqint2\*(rq) and the associated functions and operators on this new
type such that the access method can use it. Once this has been done,
@ -260,6 +260,7 @@ and
represent the use of
.IR "functional indices"
to simulate multi-key indices.
These are no longer needed now that multi-key indexes are supported.
.PP
The Postgres query optimizer will consider using btree indices in a scan
whenever an indexed attribute is involved in a comparison using one of:

9
src/man/vacuum.l
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@ -1,12 +1,12 @@
.\" This is -*-nroff-*-
.\" XXX standard disclaimer belongs here....
.\" $Header: /cvsroot/pgsql/src/man/Attic/vacuum.l,v 1.3 1997/01/13 03:45:33 momjian Exp $
.\" $Header: /cvsroot/pgsql/src/man/Attic/vacuum.l,v 1.4 1997/05/13 04:41:54 momjian Exp $
.TH VACUUM SQL 11/05/95 PostgreSQL PostgreSQL
.SH NAME
vacuum \(em vacuum a database
.SH SYNOPSIS
.nf
\fBvacuum [verbose] [\fPtable\fB]\fP
\fBvacuum [verbose] [analyze] [\fPtable [(column,...)]\fB]\fP
.fi
.SH DESCRIPTION
.BR Vacuum
@ -20,6 +20,11 @@ periodically will increase Postgres's speed in processing user queries.
.PP
\fBverbose\fP prints a detailed vacuum activity report for each table.
.PP
\fBanalyze\fP also updates column statistics used by the optimizer to
determine the most efficient way to execute a query.
The statistics represent the disbursion of the data in each column.
This information is valuable when several execution paths are possible.
.PP
The open database is the one that is vacuumed.
.PP
We recommend that production databases be vacuumed nightly, in order