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Overview
Comment:Updates to the VACUUM documentation. Ticket #2257. (CVS 3728)
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SHA1: c61c97c978dab7535c94033631f5ad2355c55057
User & Date: drh 2007-03-27 15:00:31.000
Context
2007-03-27
16:19
Test handling of IO errors that occur in OsDelete() or OsTruncate() operations. Also use an anonymous file for temporary storage during a VACUUM. (CVS 3729) (check-in: b24a6e7b02 user: danielk1977 tags: trunk)
15:00
Updates to the VACUUM documentation. Ticket #2257. (CVS 3728) (check-in: c61c97c978 user: drh tags: trunk)
14:44
The -DSQLITE_OMIT_ATTACH=1 option now omits both the ATTACH and VACUUM commands. Ticket #2268. The regression test suite depends on both of these commands and will not run if compiled with this option. (CVS 3727) (check-in: cbebfb8960 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to www/lang.tcl. 
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#
# Run this Tcl script to generate the lang-*.html files.
#
set rcsid {$Id: lang.tcl,v 1.126 2007/03/17 18:22:58 drh Exp $}
source common.tcl

if {[llength $argv]>0} {
  set outputdir [lindex $argv 0]
} else {
  set outputdir ""
}




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#
# Run this Tcl script to generate the lang-*.html files.
#
set rcsid {$Id: lang.tcl,v 1.127 2007/03/27 15:00:31 drh Exp $}
source common.tcl

if {[llength $argv]>0} {
  set outputdir [lindex $argv 0]
} else {
  set outputdir ""
}
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inserts and deletes can leave the database file structure fragmented, 
which slows down disk access to the database contents.

The VACUUM command cleans
the main database by copying its contents to a temporary database file and 
reloading the original database file from the copy.  This eliminates 
free pages,  aligns table data to be contiguous, and otherwise cleans 
up the database file structure. It is not possible to perform the same


process on an attached database file.</p>

<p>This command will fail if there is an active transaction.  This 
command has no effect on an in-memory database.</p>

<p>As of SQLite version 3.1, an alternative to using the VACUUM command
is auto-vacuum mode, enabled using the 
<a href="pragma.html#pragma_auto_vacuum">auto_vacuum pragma</a>.</p>






}

# A list of keywords.  A asterisk occurs after the keyword if it is on
# the fallback list.
#
set keyword_list [lsort {
   ABORT*








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inserts and deletes can leave the database file structure fragmented, 
which slows down disk access to the database contents.

The VACUUM command cleans
the main database by copying its contents to a temporary database file and 
reloading the original database file from the copy.  This eliminates 
free pages,  aligns table data to be contiguous, and otherwise cleans 
up the database file structure.</p>

<p>VACUUM only works on the main database.
It is not possible to VACUUM an attached database file.</p>

<p>The VACUUM command will fail if there is an active transaction.
The VACUUM command is a no-op for in-memory databases.</p>

<p>As of SQLite version 3.1, an alternative to using the VACUUM command
is auto-vacuum mode, enabled using the 
<a href="pragma.html#pragma_auto_vacuum">auto_vacuum pragma</a>.
When auto-vacuum is enabled for a database, large deletes cause
the size of the database file to shrink.  However, auto-vacuum
also causes excess fragmentation of the database file.  And auto-vacuum
does not compact partially filled pages of the database as VACUUM
does.
</p>
}

# A list of keywords.  A asterisk occurs after the keyword if it is on
# the fallback list.
#
set keyword_list [lsort {
   ABORT*
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