MySQL数据库下.frm .MYD .MYI损坏恢复操作

% myisamchk /usr/local/mysql/var/dbName/tblName
% myisamchk /usr/local/mysql/var/dbName/tblName.MYI

% myisamchk /usr/local/mysql/var/dbName/*.MYI

% myisamchk /usr/local/mysql/var/*/*.MYI

% myisamchk --extend-check /path/to/tblName

D:\Documents and Settings\Administrator>c:
C:\>cd mysql
C:\mysql>cd data
C:\mysql\data>cd hw_enterprice
C:\mysql\data\hw_enterprice>myisamchk function_products.frm
'myisamchk' 不是内部或外部命令，也不是可运行的程序
或批处理文件。
C:\mysql\data\hw_enterprice>cd\
C:\>cd mysql
C:\mysql>cd bin
注：查看myisamchk的帮助信息
C:\mysql\bin>myisamchk
myisamchk  Ver 2.6 for Win95/Win98 at i32
By Monty, for your professional use
This software comes with NO WARRANTY: see the PUBLIC for details.

Description, check and repair of ISAM tables.
Used without options all tables on the command will be checked for errors
Usage: myisamchk [OPTIONS] tables[.MYI]

Global options:
  -#, --debug=...     Output debug log. Often this is 'd:t:o,filename'
  -?, --help          Display this help and exit.
  -O, --set-variable var=option
                      Change the value of a variable. Please note that
                      this option is deprecated; you can set variables
                      directly with '--variable-name=value'.
  -t, --tmpdir=path   Path for temporary files
  -s, --silent        Only print errors.  One can use two -s to make
                      myisamchk very silent
  -v, --verbose       Print more information. This can be used with
                      --description and --check. Use many -v for more verbosity!

  -V, --version       Print version and exit.
  -w, --wait          Wait if table is locked.

Check options (check is the default action for myisamchk):
  -c, --check         Check table for errors
  -e, --extend-check  Check the table VERY throughly.  Only use this in
                      extreme cases as myisamchk should normally be able to
                      find out if the table is ok even without this switch
  -F, --fast          Check only tables that haven't been closed properly
  -C, --check-only-changed
                      Check only tables that have changed since last check
  -f, --force         Restart with '-r' if there are any errors in the table.
                      States will be updated as with '--update-state'
  -i, --information   Print statistics information about table that is checked
  -m, --medium-check  Faster than extend-check, but only finds 99.99% of
                      all errors.  Should be good enough for most cases
  -U  --update-state  Mark tables as crashed if you find any errors
  -T, --read-only     Don't mark table as checked

Repair options (When using '-r' or '-o')
  -B, --backup        Make a backup of the .MYD file as 'filename-time.BAK'
  --correct-checksum  Correct checksum information for table.
  -D, --data-file-length=#  Max length of data file (when recreating data
                      file when it's full)
  -e, --extend-check  Try to recover every possible row from the data file
                      Normally this will also find a lot of garbage rows;
                      Don't use this option if you are not totally desperate.
  -f, --force         Overwrite old temporary files.
  -k, --keys-used=#   Tell MyISAM to update only some specific keys. # is a
                      bit mask of which keys to use. This can be used to
                      get faster inserts!
  -r, --recover       Can fix almost anything except unique keys that aren't
                      unique.
  -n, --sort-recover  Forces recovering with sorting even if the temporary
                      file would be very big.
  -p, --parallel-recover
                      Uses the same technique as '-r' and '-n', but creates
                      all the keys in parallel, in different threads.
                      THIS IS ALPHA CODE. USE AT YOUR OWN RISK!
  -o, --safe-recover  Uses old recovery method; Slower than '-r' but can
                      handle a couple of cases where '-r' reports that it
                      can't fix the data file.
  --character-sets-dir=...
                      Directory where character sets are
  --set-character-set=name
                      Change the character set used by the index
  -q, --quick         Faster repair by not modifying the data file.
                      One can give a second '-q' to force myisamchk to
                      modify the original datafile in case of duplicate keys
  -u, --unpack        Unpack file packed with myisampack.

Other actions:
  -a, --analyze       Analyze distribution of keys. Will make some joins in
                      MySQL faster.  You can check the calculated distribution
                      by using '--description --verbose table_name'.
  -d, --description   Prints some information about table.
  -A, --set-auto-increment[=value]
                      Force auto_increment to start at this or higher value
                      If no value is given, then sets the next auto_increment
                      value to the highest used value for the auto key + 1.
  -S, --sort-index    Sort index blocks.  This speeds up 'read-next' in
                      applications
  -R, --sort-records=#
                      Sort records according to an index.  This makes your
                      data much more localized and may speed up things
C:\mysql\bin>myisamchk c:\mysql\data\hw_enterprice\function_products.frm
myisamchk: error: 'c:\mysql\data\hw_enterprice\function_products.frm' is not a M
yISAM-table

C:\mysql\bin>myisamchk c:\mysql\data\hw_enterprice\function_products.myi
Checking MyISAM file: c:\mysql\data\hw_enterprice\function_products.myi
Data records:   85207   Deleted blocks:      39
myisamchk: warning: Table is marked as crashed
myisamchk: warning: 1 clients is using or hasn't closed the table properly
- check file-size
- check key delete-chain
- check record delete-chain
myisamchk: error: record delete-link-chain corrupted
- check index reference
- check data record references index: 1
- check data record references index: 2
- check data record references index: 3
- check record links
myisamchk: error: Wrong bytesec: 0-195-171 at linkstart: 841908
MyISAM-table 'c:\mysql\data\hw_enterprice\function_products.myi' is corrupted
Fix it using switch "-r" or "-o"

C:\mysql\bin>myisamchk --recover --quick  c:\mysql\data\hw_enterprice\function_p
roducts.myi
- check key delete-chain
- check record delete-chain
myisamchk: error: record delete-link-chain corrupted
myisamchk: error: Quick-recover aborted; Run recovery without switch 'q'
Updating MyISAM file: c:\mysql\data\hw_enterprice\function_products.myi
MyISAM-table 'c:\mysql\data\hw_enterprice\function_products.myi' is not fixed be
cause of errors
Try fixing it by using the --safe-recover (-o) or the --force (-f) option

C:\mysql\bin>myisamchk --safe-recover  c:\mysql\data\hw_enterprice\function_prod
ucts.myi
- recovering (with keycache) MyISAM-table 'c:\mysql\data\hw_enterprice\function_
products.myi'
Data records: 85207
Wrong bytesec:   0-195-171 at     841908; Skipped
Data records: 85215

% myisamchk --recover --quick /path/to/tblName
% myisamchk --recover /path/to/tblName
% myisamchk --safe-recover /path/to/tblName

mysql> DELETE FROM tblName;