aria_pack
Contents
aria_pack is a tool for compressing Aria tables. The resulting table are read-only, and usually about 40% to 70% smaller.
aria_pack is run as follows
aria_pack [options] file_name [file_name2...]
The file name is the .MAI index file. The extension can be omitted, although keeping it permits wildcards, such as
aria_pack *.MAI
to compress all the files.
aria_pack compresses each column separately, and, when the resulting data is read, only the individual rows and columns required need to be decompressed, allowing for quicker reading.
Once a table has been packed, use aria_chk -rq (the quick and recover options) to rebuild its indexes.
Options
The following variables can be set while passed as commandline options to aria_pack, or set in the [ariapack] section in your my.cnf file.
| Option | Description |
|---|---|
| -b, --backup | Make a backup of the table as table_name.OLD. |
| --character-sets-dir=name | Directory where character sets are. |
| -#, --debug[=name] | Output debug log. Often this is 'd:t:o,filename'. |
| -f, --force | Force packing of table even if it gets bigger or if tempfile exists. |
| -j, --join=name | Join all given tables into 'new_table_name'. All tables MUST have identical layouts. |
| -?, --help | Display help and exit. |
| -s, --silent | Only write output when an error occurs. |
| -T, --tmpdir=name | Use temporary directory to store temporary table. |
| -t, --test | Don't pack table, only test packing it. |
| -v, --verbose | Write info about progress and packing result. Use many -v for more verbosity! |
| -V, --version | Output version information and exit. |
| -w, --wait | Wait and retry if table is in use. |
Uncompressing
To uncompress a table compressed with aria_pack, use the aria_chk -u option.
Example
> aria_pack /my/data/test/posts Compressing /my/data/test/posts.MAD: (1690 records) - Calculating statistics - Compressing file 37.71% > aria_chk -rq --ignore-control-file /my/data/test/posts - check record delete-chain - recovering (with keycache) Aria-table '/my/data/test/posts' Data records: 1690 State updated
