MySQL数据库中部分数据损坏恢复过程

注：此为记录我当时操作的全部过程 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