858 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			Groff
		
	
	
	
		
		
			
		
	
	
			858 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			Groff
		
	
	
	
|  | '\" t | ||
|  | .\"     Title: \fBmyisampack\fR | ||
|  | .\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author] | ||
|  | .\" Generator: DocBook XSL Stylesheets v1.77.1 <http://docbook.sf.net/> | ||
|  | .\"      Date: 11/04/2013 | ||
|  | .\"    Manual: MySQL Database System | ||
|  | .\"    Source: MySQL 5.1 | ||
|  | .\"  Language: English | ||
|  | .\" | ||
|  | .TH "\FBMYISAMPACK\FR" "1" "11/04/2013" "MySQL 5\&.1" "MySQL Database System" | ||
|  | .\" ----------------------------------------------------------------- | ||
|  | .\" * Define some portability stuff | ||
|  | .\" ----------------------------------------------------------------- | ||
|  | .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | ||
|  | .\" http://bugs.debian.org/507673 | ||
|  | .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html | ||
|  | .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | ||
|  | .ie \n(.g .ds Aq \(aq | ||
|  | .el       .ds Aq ' | ||
|  | .\" ----------------------------------------------------------------- | ||
|  | .\" * set default formatting | ||
|  | .\" ----------------------------------------------------------------- | ||
|  | .\" disable hyphenation | ||
|  | .nh | ||
|  | .\" disable justification (adjust text to left margin only) | ||
|  | .ad l | ||
|  | .\" ----------------------------------------------------------------- | ||
|  | .\" * MAIN CONTENT STARTS HERE * | ||
|  | .\" ----------------------------------------------------------------- | ||
|  | .\" myisampack | ||
|  | .\" compressed tables | ||
|  | .\" tables: compressed | ||
|  | .\" MyISAM: compressed tables | ||
|  | .SH "NAME" | ||
|  | myisampack \- generate compressed, read\-only MyISAM tables | ||
|  | .SH "SYNOPSIS" | ||
|  | .HP \w'\fBmyisampack\ [\fR\fB\fIoptions\fR\fR\fB]\ \fR\fB\fIfile_name\fR\fR\fB\ \&.\&.\&.\fR\ 'u | ||
|  | \fBmyisampack [\fR\fB\fIoptions\fR\fR\fB] \fR\fB\fIfile_name\fR\fR\fB \&.\&.\&.\fR | ||
|  | .SH "DESCRIPTION" | ||
|  | .PP | ||
|  | The | ||
|  | \fBmyisampack\fR | ||
|  | utility compresses | ||
|  | MyISAM | ||
|  | tables\&. | ||
|  | \fBmyisampack\fR | ||
|  | works by compressing each column in the table separately\&. Usually, | ||
|  | \fBmyisampack\fR | ||
|  | packs the data file 40% to 70%\&. | ||
|  | .PP | ||
|  | When the table is used later, the server reads into memory the information needed to decompress columns\&. This results in much better performance when accessing individual rows, because you only have to uncompress exactly one row\&. | ||
|  | .PP | ||
|  | MySQL uses | ||
|  | mmap() | ||
|  | when possible to perform memory mapping on compressed tables\&. If | ||
|  | mmap() | ||
|  | does not work, MySQL falls back to normal read/write file operations\&. | ||
|  | .PP | ||
|  | Please note the following: | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | If the | ||
|  | \fBmysqld\fR | ||
|  | server was invoked with external locking disabled, it is not a good idea to invoke | ||
|  | \fBmyisampack\fR | ||
|  | if the table might be updated by the server during the packing process\&. It is safest to compress tables with the server stopped\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | After packing a table, it becomes read only\&. This is generally intended (such as when accessing packed tables on a CD)\&. | ||
|  | .RE | ||
|  | .PP | ||
|  | Invoke | ||
|  | \fBmyisampack\fR | ||
|  | like this: | ||
|  | .sp | ||
|  | .if n \{\ | ||
|  | .RS 4 | ||
|  | .\} | ||
|  | .nf | ||
|  | shell> \fBmyisampack [\fR\fB\fIoptions\fR\fR\fB] \fR\fB\fIfile_name\fR\fR\fB \&.\&.\&.\fR | ||
|  | .fi | ||
|  | .if n \{\ | ||
|  | .RE | ||
|  | .\} | ||
|  | .PP | ||
|  | Each file name argument should be the name of an index (\&.MYI) file\&. If you are not in the database directory, you should specify the path name to the file\&. It is permissible to omit the | ||
|  | \&.MYI | ||
|  | extension\&. | ||
|  | .PP | ||
|  | After you compress a table with | ||
|  | \fBmyisampack\fR, you should use | ||
|  | \fBmyisamchk \-rq\fR | ||
|  | to rebuild its indexes\&. | ||
|  | \fBmyisamchk\fR(1)\&. | ||
|  | .PP | ||
|  | \fBmyisampack\fR | ||
|  | supports the following options\&. It also reads option files and supports the options for processing them described at | ||
|  | Section\ \&4.2.3.4, \(lqCommand-Line Options that Affect Option-File Handling\(rq\&. | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: help option | ||
|  | .\" help option: myisampack | ||
|  | \fB\-\-help\fR, | ||
|  | \fB\-?\fR | ||
|  | .sp | ||
|  | Display a help message and exit\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: backup option | ||
|  | .\" backup option: myisampack | ||
|  | \fB\-\-backup\fR, | ||
|  | \fB\-b\fR | ||
|  | .sp | ||
|  | Make a backup of each table\*(Aqs data file using the name | ||
|  | \fItbl_name\fR\&.OLD\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: character-sets-dir option | ||
|  | .\" character-sets-dir option: myisampack | ||
|  | \fB\-\-character\-sets\-dir=\fR\fB\fIpath\fR\fR | ||
|  | .sp | ||
|  | The directory where character sets are installed\&. See | ||
|  | Section\ \&10.5, \(lqCharacter Set Configuration\(rq\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: debug option | ||
|  | .\" debug option: myisampack | ||
|  | \fB\-\-debug[=\fR\fB\fIdebug_options\fR\fR\fB]\fR, | ||
|  | \fB\-# [\fR\fB\fIdebug_options\fR\fR\fB]\fR | ||
|  | .sp | ||
|  | Write a debugging log\&. A typical | ||
|  | \fIdebug_options\fR | ||
|  | string is | ||
|  | \*(Aqd:t:o,\fIfile_name\fR\*(Aq\&. The default is | ||
|  | \*(Aqd:t:o\*(Aq\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: force option | ||
|  | .\" force option: myisampack | ||
|  | \fB\-\-force\fR, | ||
|  | \fB\-f\fR | ||
|  | .sp | ||
|  | Produce a packed table even if it becomes larger than the original or if the intermediate file from an earlier invocation of | ||
|  | \fBmyisampack\fR | ||
|  | exists\&. (\fBmyisampack\fR | ||
|  | creates an intermediate file named | ||
|  | \fItbl_name\fR\&.TMD | ||
|  | in the database directory while it compresses the table\&. If you kill | ||
|  | \fBmyisampack\fR, the | ||
|  | \&.TMD | ||
|  | file might not be deleted\&.) Normally, | ||
|  | \fBmyisampack\fR | ||
|  | exits with an error if it finds that | ||
|  | \fItbl_name\fR\&.TMD | ||
|  | exists\&. With | ||
|  | \fB\-\-force\fR, | ||
|  | \fBmyisampack\fR | ||
|  | packs the table anyway\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: join option | ||
|  | .\" join option: myisampack | ||
|  | \fB\-\-join=\fR\fB\fIbig_tbl_name\fR\fR, | ||
|  | \fB\-j \fR\fB\fIbig_tbl_name\fR\fR | ||
|  | .sp | ||
|  | Join all tables named on the command line into a single packed table | ||
|  | \fIbig_tbl_name\fR\&. All tables that are to be combined | ||
|  | \fImust\fR | ||
|  | have identical structure (same column names and types, same indexes, and so forth)\&. | ||
|  | .sp | ||
|  | \fIbig_tbl_name\fR | ||
|  | must not exist prior to the join operation\&. All source tables named on the command line to be merged into | ||
|  | \fIbig_tbl_name\fR | ||
|  | must exist\&. The source tables are read for the join operation but not modified\&. The join operation does not create a | ||
|  | \&.frm | ||
|  | file for | ||
|  | \fIbig_tbl_name\fR, so after the join operation finishes, copy the | ||
|  | \&.frm | ||
|  | file from one of the source tables and name it | ||
|  | \fIbig_tbl_name\fR\&.frm\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: silent option | ||
|  | .\" silent option: myisampack | ||
|  | \fB\-\-silent\fR, | ||
|  | \fB\-s\fR | ||
|  | .sp | ||
|  | Silent mode\&. Write output only when errors occur\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: test option | ||
|  | .\" test option: myisampack | ||
|  | \fB\-\-test\fR, | ||
|  | \fB\-t\fR | ||
|  | .sp | ||
|  | Do not actually pack the table, just test packing it\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: tmpdir option | ||
|  | .\" tmpdir option: myisampack | ||
|  | \fB\-\-tmpdir=\fR\fB\fIpath\fR\fR, | ||
|  | \fB\-T \fR\fB\fIpath\fR\fR | ||
|  | .sp | ||
|  | Use the named directory as the location where | ||
|  | \fBmyisampack\fR | ||
|  | creates temporary files\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: verbose option | ||
|  | .\" verbose option: myisampack | ||
|  | \fB\-\-verbose\fR, | ||
|  | \fB\-v\fR | ||
|  | .sp | ||
|  | Verbose mode\&. Write information about the progress of the packing operation and its result\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: version option | ||
|  | .\" version option: myisampack | ||
|  | \fB\-\-version\fR, | ||
|  | \fB\-V\fR | ||
|  | .sp | ||
|  | Display version information and exit\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | .\" myisampack: wait option | ||
|  | .\" wait option: myisampack | ||
|  | \fB\-\-wait\fR, | ||
|  | \fB\-w\fR | ||
|  | .sp | ||
|  | Wait and retry if the table is in use\&. If the | ||
|  | \fBmysqld\fR | ||
|  | server was invoked with external locking disabled, it is not a good idea to invoke | ||
|  | \fBmyisampack\fR | ||
|  | if the table might be updated by the server during the packing process\&. | ||
|  | .RE | ||
|  | .\" examples: compressed tables | ||
|  | .PP | ||
|  | The following sequence of commands illustrates a typical table compression session: | ||
|  | .sp | ||
|  | .if n \{\ | ||
|  | .RS 4 | ||
|  | .\} | ||
|  | .nf | ||
|  | shell> \fBls \-l station\&.*\fR | ||
|  | \-rw\-rw\-r\-\-   1 monty    my         994128 Apr 17 19:00 station\&.MYD | ||
|  | \-rw\-rw\-r\-\-   1 monty    my          53248 Apr 17 19:00 station\&.MYI | ||
|  | \-rw\-rw\-r\-\-   1 monty    my           5767 Apr 17 19:00 station\&.frm | ||
|  | shell> \fBmyisamchk \-dvv station\fR | ||
|  | MyISAM file:     station | ||
|  | Isam\-version:  2 | ||
|  | Creation time: 1996\-03\-13 10:08:58 | ||
|  | Recover time:  1997\-02\-02  3:06:43 | ||
|  | Data records:              1192  Deleted blocks:              0 | ||
|  | Datafile parts:            1192  Deleted data:                0 | ||
|  | Datafile pointer (bytes):     2  Keyfile pointer (bytes):     2 | ||
|  | Max datafile length:   54657023  Max keyfile length:   33554431 | ||
|  | Recordlength:               834 | ||
|  | Record format: Fixed length | ||
|  | table description: | ||
|  | Key Start Len Index   Type                 Root  Blocksize    Rec/key | ||
|  | 1   2     4   unique  unsigned long        1024       1024          1 | ||
|  | 2   32    30  multip\&. text                10240       1024          1 | ||
|  | Field Start Length Type | ||
|  | 1     1     1 | ||
|  | 2     2     4 | ||
|  | 3     6     4 | ||
|  | 4     10    1 | ||
|  | 5     11    20 | ||
|  | 6     31    1 | ||
|  | 7     32    30 | ||
|  | 8     62    35 | ||
|  | 9     97    35 | ||
|  | 10    132   35 | ||
|  | 11    167   4 | ||
|  | 12    171   16 | ||
|  | 13    187   35 | ||
|  | 14    222   4 | ||
|  | 15    226   16 | ||
|  | 16    242   20 | ||
|  | 17    262   20 | ||
|  | 18    282   20 | ||
|  | 19    302   30 | ||
|  | 20    332   4 | ||
|  | 21    336   4 | ||
|  | 22    340   1 | ||
|  | 23    341   8 | ||
|  | 24    349   8 | ||
|  | 25    357   8 | ||
|  | 26    365   2 | ||
|  | 27    367   2 | ||
|  | 28    369   4 | ||
|  | 29    373   4 | ||
|  | 30    377   1 | ||
|  | 31    378   2 | ||
|  | 32    380   8 | ||
|  | 33    388   4 | ||
|  | 34    392   4 | ||
|  | 35    396   4 | ||
|  | 36    400   4 | ||
|  | 37    404   1 | ||
|  | 38    405   4 | ||
|  | 39    409   4 | ||
|  | 40    413   4 | ||
|  | 41    417   4 | ||
|  | 42    421   4 | ||
|  | 43    425   4 | ||
|  | 44    429   20 | ||
|  | 45    449   30 | ||
|  | 46    479   1 | ||
|  | 47    480   1 | ||
|  | 48    481   79 | ||
|  | 49    560   79 | ||
|  | 50    639   79 | ||
|  | 51    718   79 | ||
|  | 52    797   8 | ||
|  | 53    805   1 | ||
|  | 54    806   1 | ||
|  | 55    807   20 | ||
|  | 56    827   4 | ||
|  | 57    831   4 | ||
|  | shell> \fBmyisampack station\&.MYI\fR | ||
|  | Compressing station\&.MYI: (1192 records) | ||
|  | \- Calculating statistics | ||
|  | normal:     20  empty\-space:   16  empty\-zero:     12  empty\-fill:  11 | ||
|  | pre\-space:   0  end\-space:     12  table\-lookups:   5  zero:         7 | ||
|  | Original trees:  57  After join: 17 | ||
|  | \- Compressing file | ||
|  | 87\&.14% | ||
|  | Remember to run myisamchk \-rq on compressed tables | ||
|  | shell> \fBls \-l station\&.*\fR | ||
|  | \-rw\-rw\-r\-\-   1 monty    my         127874 Apr 17 19:00 station\&.MYD | ||
|  | \-rw\-rw\-r\-\-   1 monty    my          55296 Apr 17 19:04 station\&.MYI | ||
|  | \-rw\-rw\-r\-\-   1 monty    my           5767 Apr 17 19:00 station\&.frm | ||
|  | shell> \fBmyisamchk \-dvv station\fR | ||
|  | MyISAM file:     station | ||
|  | Isam\-version:  2 | ||
|  | Creation time: 1996\-03\-13 10:08:58 | ||
|  | Recover time:  1997\-04\-17 19:04:26 | ||
|  | Data records:               1192  Deleted blocks:              0 | ||
|  | Datafile parts:             1192  Deleted data:                0 | ||
|  | Datafile pointer (bytes):      3  Keyfile pointer (bytes):     1 | ||
|  | Max datafile length:    16777215  Max keyfile length:     131071 | ||
|  | Recordlength:                834 | ||
|  | Record format: Compressed | ||
|  | table description: | ||
|  | Key Start Len Index   Type                 Root  Blocksize    Rec/key | ||
|  | 1   2     4   unique  unsigned long       10240       1024          1 | ||
|  | 2   32    30  multip\&. text                54272       1024          1 | ||
|  | Field Start Length Type                         Huff tree  Bits | ||
|  | 1     1     1      constant                             1     0 | ||
|  | 2     2     4      zerofill(1)                          2     9 | ||
|  | 3     6     4      no zeros, zerofill(1)                2     9 | ||
|  | 4     10    1                                           3     9 | ||
|  | 5     11    20     table\-lookup                         4     0 | ||
|  | 6     31    1                                           3     9 | ||
|  | 7     32    30     no endspace, not_always              5     9 | ||
|  | 8     62    35     no endspace, not_always, no empty    6     9 | ||
|  | 9     97    35     no empty                             7     9 | ||
|  | 10    132   35     no endspace, not_always, no empty    6     9 | ||
|  | 11    167   4      zerofill(1)                          2     9 | ||
|  | 12    171   16     no endspace, not_always, no empty    5     9 | ||
|  | 13    187   35     no endspace, not_always, no empty    6     9 | ||
|  | 14    222   4      zerofill(1)                          2     9 | ||
|  | 15    226   16     no endspace, not_always, no empty    5     9 | ||
|  | 16    242   20     no endspace, not_always              8     9 | ||
|  | 17    262   20     no endspace, no empty                8     9 | ||
|  | 18    282   20     no endspace, no empty                5     9 | ||
|  | 19    302   30     no endspace, no empty                6     9 | ||
|  | 20    332   4      always zero                          2     9 | ||
|  | 21    336   4      always zero                          2     9 | ||
|  | 22    340   1                                           3     9 | ||
|  | 23    341   8      table\-lookup                         9     0 | ||
|  | 24    349   8      table\-lookup                        10     0 | ||
|  | 25    357   8      always zero                          2     9 | ||
|  | 26    365   2                                           2     9 | ||
|  | 27    367   2      no zeros, zerofill(1)                2     9 | ||
|  | 28    369   4      no zeros, zerofill(1)                2     9 | ||
|  | 29    373   4      table\-lookup                        11     0 | ||
|  | 30    377   1                                           3     9 | ||
|  | 31    378   2      no zeros, zerofill(1)                2     9 | ||
|  | 32    380   8      no zeros                             2     9 | ||
|  | 33    388   4      always zero                          2     9 | ||
|  | 34    392   4      table\-lookup                        12     0 | ||
|  | 35    396   4      no zeros, zerofill(1)               13     9 | ||
|  | 36    400   4      no zeros, zerofill(1)                2     9 | ||
|  | 37    404   1                                           2     9 | ||
|  | 38    405   4      no zeros                             2     9 | ||
|  | 39    409   4      always zero                          2     9 | ||
|  | 40    413   4      no zeros                             2     9 | ||
|  | 41    417   4      always zero                          2     9 | ||
|  | 42    421   4      no zeros                             2     9 | ||
|  | 43    425   4      always zero                          2     9 | ||
|  | 44    429   20     no empty                             3     9 | ||
|  | 45    449   30     no empty                             3     9 | ||
|  | 46    479   1                                          14     4 | ||
|  | 47    480   1                                          14     4 | ||
|  | 48    481   79     no endspace, no empty               15     9 | ||
|  | 49    560   79     no empty                             2     9 | ||
|  | 50    639   79     no empty                             2     9 | ||
|  | 51    718   79     no endspace                         16     9 | ||
|  | 52    797   8      no empty                             2     9 | ||
|  | 53    805   1                                          17     1 | ||
|  | 54    806   1                                           3     9 | ||
|  | 55    807   20     no empty                             3     9 | ||
|  | 56    827   4      no zeros, zerofill(2)                2     9 | ||
|  | 57    831   4      no zeros, zerofill(1)                2     9 | ||
|  | .fi | ||
|  | .if n \{\ | ||
|  | .RE | ||
|  | .\} | ||
|  | .PP | ||
|  | \fBmyisampack\fR | ||
|  | displays the following kinds of information: | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | normal | ||
|  | .sp | ||
|  | The number of columns for which no extra packing is used\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | empty\-space | ||
|  | .sp | ||
|  | The number of columns containing values that are only spaces\&. These occupy one bit\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | empty\-zero | ||
|  | .sp | ||
|  | The number of columns containing values that are only binary zeros\&. These occupy one bit\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | empty\-fill | ||
|  | .sp | ||
|  | The number of integer columns that do not occupy the full byte range of their type\&. These are changed to a smaller type\&. For example, a | ||
|  | BIGINT | ||
|  | column (eight bytes) can be stored as a | ||
|  | TINYINT | ||
|  | column (one byte) if all its values are in the range from | ||
|  | \-128 | ||
|  | to | ||
|  | 127\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | pre\-space | ||
|  | .sp | ||
|  | The number of decimal columns that are stored with leading spaces\&. In this case, each value contains a count for the number of leading spaces\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | end\-space | ||
|  | .sp | ||
|  | The number of columns that have a lot of trailing spaces\&. In this case, each value contains a count for the number of trailing spaces\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | table\-lookup | ||
|  | .sp | ||
|  | The column had only a small number of different values, which were converted to an | ||
|  | ENUM | ||
|  | before Huffman compression\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | zero | ||
|  | .sp | ||
|  | The number of columns for which all values are zero\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | Original trees | ||
|  | .sp | ||
|  | The initial number of Huffman trees\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | After join | ||
|  | .sp | ||
|  | The number of distinct Huffman trees left after joining trees to save some header space\&. | ||
|  | .RE | ||
|  | .PP | ||
|  | After a table has been compressed, the | ||
|  | Field | ||
|  | lines displayed by | ||
|  | \fBmyisamchk \-dvv\fR | ||
|  | include additional information about each column: | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | Type | ||
|  | .sp | ||
|  | The data type\&. The value may contain any of the following descriptors: | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | constant | ||
|  | .sp | ||
|  | All rows have the same value\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | no endspace | ||
|  | .sp | ||
|  | Do not store endspace\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | no endspace, not_always | ||
|  | .sp | ||
|  | Do not store endspace and do not do endspace compression for all values\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | no endspace, no empty | ||
|  | .sp | ||
|  | Do not store endspace\&. Do not store empty values\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | table\-lookup | ||
|  | .sp | ||
|  | The column was converted to an | ||
|  | ENUM\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | zerofill(\fIN\fR) | ||
|  | .sp | ||
|  | The most significant | ||
|  | \fIN\fR | ||
|  | bytes in the value are always 0 and are not stored\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | no zeros | ||
|  | .sp | ||
|  | Do not store zeros\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | always zero | ||
|  | .sp | ||
|  | Zero values are stored using one bit\&. | ||
|  | .RE | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | Huff tree | ||
|  | .sp | ||
|  | The number of the Huffman tree associated with the column\&. | ||
|  | .RE | ||
|  | .sp | ||
|  | .RS 4 | ||
|  | .ie n \{\ | ||
|  | \h'-04'\(bu\h'+03'\c | ||
|  | .\} | ||
|  | .el \{\ | ||
|  | .sp -1 | ||
|  | .IP \(bu 2.3 | ||
|  | .\} | ||
|  | Bits | ||
|  | .sp | ||
|  | The number of bits used in the Huffman tree\&. | ||
|  | .RE | ||
|  | .PP | ||
|  | After you run | ||
|  | \fBmyisampack\fR, you must run | ||
|  | \fBmyisamchk\fR | ||
|  | to re\-create any indexes\&. At this time, you can also sort the index blocks and create statistics needed for the MySQL optimizer to work more efficiently: | ||
|  | .sp | ||
|  | .if n \{\ | ||
|  | .RS 4 | ||
|  | .\} | ||
|  | .nf | ||
|  | shell> \fBmyisamchk \-rq \-\-sort\-index \-\-analyze \fR\fB\fItbl_name\fR\fR\fB\&.MYI\fR | ||
|  | .fi | ||
|  | .if n \{\ | ||
|  | .RE | ||
|  | .\} | ||
|  | .PP | ||
|  | After you have installed the packed table into the MySQL database directory, you should execute | ||
|  | \fBmysqladmin flush\-tables\fR | ||
|  | to force | ||
|  | \fBmysqld\fR | ||
|  | to start using the new table\&. | ||
|  | .PP | ||
|  | To unpack a packed table, use the | ||
|  | \fB\-\-unpack\fR | ||
|  | option to | ||
|  | \fBmyisamchk\fR\&. | ||
|  | .SH "COPYRIGHT" | ||
|  | .br | ||
|  | .PP | ||
|  | Copyright \(co 1997, 2013, Oracle and/or its affiliates. All rights reserved. | ||
|  | .PP | ||
|  | This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. | ||
|  | .PP | ||
|  | This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. | ||
|  | .PP | ||
|  | You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see http://www.gnu.org/licenses/. | ||
|  | .sp | ||
|  | .SH "SEE ALSO" | ||
|  | For more information, please refer to the MySQL Reference Manual, | ||
|  | which may already be installed locally and which is also available | ||
|  | online at http://dev.mysql.com/doc/. | ||
|  | .SH AUTHOR | ||
|  | Oracle Corporation (http://dev.mysql.com/). |