Make a backup of each table’s data file using the name tbl_name .OLD . 

• --character-sets-dir= dir_name 

The directory where character sets are installed. See Section 10.15, “Character Set Configuration” . 

• --debug[= debug_options ] , -# [ debug_options ] 

Write a debugging log. A typical debug_options  string is d:t:o, file_name . The default is d:t:o . 

This option is available only if MySQL was built using WITH_DEBUG . MySQL release binaries provided by Oracle are not  built using this option. 

• --force , -f 

Produce a packed table even if it becomes larger than the original or if the intermediate file from an earlier invocation of myisampack  exists. ( myisampack  creates an intermediate file named tbl_name .TMD  in the database directory while it compresses the table. If you kill myisampack , the .TMD  file might not be deleted.) Normally, myisampack  exits with an error if it finds that tbl_name .TMD exists. With --force , myisampack  packs the table anyway. 

• --join= big_tbl_name , -j big_tbl_name 

Join all tables named on the command line into a single packed table big_tbl_name . All tables that are to be combined must  have identical structure (same column names and types, same indexes, and so forth). 

big_tbl_name  must not exist prior to the join operation. All source tables named on the command line to be merged into big_tbl_name  must exist. The source tables are read for the join operation but not modified. 

• --silent , -s 

Silent mode. Write output only when errors occur. 

• --test , -t 

Do not actually pack the table, just test packing it. 

• --tmpdir= dir_name , -T dir_name 

Use the named directory as the location where myisampack  creates temporary files. 

• --verbose , -v 

Verbose mode. Write information about the progress of the packing operation and its result. 

• --version , -V 

Display version information and exit. 

• --wait , -w 

Wait and retry if the table is in use. If the mysqld  server was invoked with external locking disabled, it is not a good idea to invoke myisampack  if the table might be updated by the server during the packing process. 

