XAPIAN-COMPACT(1) User Commands XAPIAN-COMPACT(1)NAME
xapian-compact - Compact a database, or merge and compact several
SYNOPSIS
xapian-compact [OPTIONS] SOURCE_DATABASE... DESTINATION_DATABASE
DESCRIPTION
xapian-compact - Compact a database, or merge and compact several
OPTIONS -b, --blocksize
Set the blocksize in bytes (e.g. 4096) or K (e.g. 4K) (must be between 2K and 64K and a power of 2, default 8K)
-n, --no-full
Disable full compaction
-F, --fuller
Enable fuller compaction (not recommended if you plan to update the compacted database)
-m, --multipass
If merging more than 3 databases, merge the postlists in multiple passes (which is generally faster but requires more disk space for
temporary files)
--no-renumber Preserve the numbering of document ids (useful if you have
external references to them, or have set them to match unique ids from an external source). Currently this option is only supported
when merging databases if they have disjoint ranges of used document ids
--help display this help and exit
--version
output version information and exit
xapian-core 1.2.12 June 2012 XAPIAN-COMPACT(1)
Check Out this Related Man Page
compact(1) General Commands Manual compact(1)Name
compact, uncompact, ccat - compress and uncompress files, and cat them
Syntax
compact [name...]
uncompact [name...]
ccat [file...]
Description
The command compresses the named files using an adaptive Huffman code. If no file names are given, the standard input is compacted to the
standard output. The command operates as an on-line algorithm. Each time a byte is read, it is encoded immediately according to the cur-
rent prefix code. This code is an optimal Huffman code for the set of frequencies seen so far. It is unnecessary to prepend a decoding
tree to the compressed file since the encoder and the decoder start in the same state and stay synchronized. Furthermore, and can operate
as filters. In particular,
... | compact | uncompact | ...
operates as a (very slow) no-op.
When an argument file is given, it is compacted and the resulting file is placed in file.C; file is unlinked. The first two bytes of the
compacted file code the fact that the file is compacted. This code is used to prohibit recompaction.
The amount of compression to be expected depends on the type of file being compressed. Typical values of compression are: Text (38%), Pas-
cal Source (43%), C Source (36%) and Binary (19%). These values are the percentages of file bytes reduced.
The command restores the original file from a file compressed by If no file names are given, the standard input is uncompacted to the stan-
dard output.
The command cats the original file from a file compressed by without uncompressing the file.
The command is present only for compatibility. In general, the command runs faster and gives better compression.
Restrictions
The last segment of the file name must contain fewer than thirteen characters to allow space for the appended '.C'.
Files
compacted file created by compact, removed by uncompact
See Alsocompress(1)compact(1)
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