6.6.3 myisam_ftdump — Display Full-Text Index information

myisam_ftdump displays information about FULLTEXT indexes in MyISAM tables. It reads the MyISAM index file directly, so it must be run on the server host where the table is located. Before using myisam_ftdump, be sure to issue a FLUSH TABLES statement first if the server is running.

myisam_ftdump scans and dumps the entire index, which is not particularly fast. On the other hand, the distribution of words changes infrequently, so it need not be run often.

Invoke myisam_ftdump like this:

myisam_ftdump [options] tbl_name index_num

The tbl_name argument should be the name of a MyISAM table. You can also specify a table by naming its index file (the file with the .MYI suffix). If you do not invoke myisam_ftdump in the directory where the table files are located, the table or index file name must be preceded by the path name to the table's database directory. Index numbers begin with 0.

Example: Suppose that the test database contains a table named mytexttable that has the following definition:

CREATE TABLE mytexttable
(
  id   INT NOT NULL,
  txt  TEXT NOT NULL,
  PRIMARY KEY (id),
  FULLTEXT (txt)
) ENGINE=MyISAM;

The index on id is index 0 and the FULLTEXT index on txt is index 1. If your working directory is the test database directory, invoke myisam_ftdump as follows:

myisam_ftdump mytexttable 1

If the path name to the test database directory is /usr/local/mysql/data/test, you can also specify the table name argument using that path name. This is useful if you do not invoke myisam_ftdump in the database directory:

myisam_ftdump /usr/local/mysql/data/test/mytexttable 1

You can use myisam_ftdump to generate a list of index entries in order of frequency of occurrence like this on Unix-like systems:

myisam_ftdump -c mytexttable 1 | sort -r

On Windows, use:

myisam_ftdump -c mytexttable 1 | sort /R

myisam_ftdump supports the following options:

• --help, -h -?

  Command-Line Format	--help

  Display a help message and exit.

• --count, -c

  Command-Line Format	--count

  Calculate per-word statistics (counts and global weights).

• --dump, -d

  Command-Line Format	--dump

  Dump the index, including data offsets and word weights.

• --length, -l

  Command-Line Format	--length

  Report the length distribution.

• --stats, -s

  Command-Line Format	--stats

  Report global index statistics. This is the default operation if no other operation is specified.

• --verbose, -v

  Command-Line Format	--verbose

  Verbose mode. Print more output about what the program does.