.\" Title: \fBmysqldump\fR .\" Author: .\" Generator: DocBook XSL Stylesheets v1.70.1 .\" Date: 06/16/2009 .\" Manual: MySQL Database System .\" Source: MySQL 5.1 .\" .TH "\fBMYSQLDUMP\fR" "1" "06/16/2009" "MySQL 5.1" "MySQL Database System" .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .SH "NAME" mysqldump \- a database backup program .SH "SYNOPSIS" .HP 45 \fBmysqldump [\fR\fB\fIoptions\fR\fR\fB] [\fR\fB\fIdb_name\fR\fR\fB [\fR\fB\fItbl_name\fR\fR\fB ...]]\fR .SH "DESCRIPTION" .PP The \fBmysqldump\fR client is a backup program originally written by Igor Romanenko. It can be used to dump a database or a collection of databases for backup or transfer to another SQL server (not necessarily a MySQL server). The dump typically contains SQL statements to create the table, populate it, or both. However, \fBmysqldump\fR can also be used to generate files in CSV, other delimited text, or XML format. .PP If you are doing a backup on the server and your tables all are MyISAM tables, consider using the \fBmysqlhotcopy\fR instead because it can accomplish faster backups and faster restores. See \fBmysqlhotcopy\fR(1). .PP There are three general ways to invoke \fBmysqldump\fR: .sp .RS 3n .nf shell> \fBmysqldump [\fR\fB\fIoptions\fR\fR\fB] \fR\fB\fIdb_name\fR\fR\fB [\fR\fB\fItables\fR\fR\fB]\fR shell> \fBmysqldump [\fR\fB\fIoptions\fR\fR\fB] \-\-databases \fR\fB\fIdb_name1\fR\fR\fB [\fR\fB\fIdb_name2\fR\fR\fB \fR\fB\fIdb_name3\fR\fR\fB...]\fR shell> \fBmysqldump [\fR\fB\fIoptions\fR\fR\fB] \-\-all\-databases\fR .fi .RE .PP If you do not name any tables following \fIdb_name\fR or if you use the \fB\-\-databases\fR or \fB\-\-all\-databases\fR option, entire databases are dumped. .PP \fBmysqldump\fR does not dump the INFORMATION_SCHEMA database. If you name that database explicitly on the command line, \fBmysqldump\fR silently ignores it. .PP To get a list of the options your version of \fBmysqldump\fR supports, execute \fBmysqldump \-\-help\fR. .PP Some \fBmysqldump\fR options are shorthand for groups of other options. \fB\-\-opt\fR and \fB\-\-compact\fR fall into this category. For example, use of \fB\-\-opt\fR is the same as specifying \fB\-\-add\-drop\-table\fR \fB\-\-add\-locks\fR \fB\-\-create\-options\fR \fB\-\-disable\-keys\fR \fB\-\-extended\-insert\fR \fB\-\-lock\-tables\fR \fB\-\-quick\fR \fB\-\-set\-charset\fR. Note that all of the options that \fB\-\-opt\fR stands for also are on by default because \fB\-\-opt\fR is on by default. .PP To reverse the effect of a group option, uses its \fB\-\-skip\-\fR\fB\fIxxx\fR\fR form (\fB\-\-skip\-opt\fR or \fB\-\-skip\-compact\fR). It is also possible to select only part of the effect of a group option by following it with options that enable or disable specific features. Here are some examples: .TP 3n \(bu To select the effect of \fB\-\-opt\fR except for some features, use the \fB\-\-skip\fR option for each feature. For example, to disable extended inserts and memory buffering, use \fB\-\-opt\fR \fB\-\-skip\-extended\-insert\fR \fB\-\-skip\-quick\fR. (As of MySQL 5.1, \fB\-\-skip\-extended\-insert\fR \fB\-\-skip\-quick\fR is sufficient because \fB\-\-opt\fR is on by default.) .TP 3n \(bu To reverse \fB\-\-opt\fR for all features except index disabling and table locking, use \fB\-\-skip\-opt\fR \fB\-\-disable\-keys\fR \fB\-\-lock\-tables\fR. .sp .RE .PP When you selectively enable or disable the effect of a group option, order is important because options are processed first to last. For example, \fB\-\-disable\-keys\fR \fB\-\-lock\-tables\fR \fB\-\-skip\-opt\fR would not have the intended effect; it is the same as \fB\-\-skip\-opt\fR by itself. .PP \fBmysqldump\fR can retrieve and dump table contents row by row, or it can retrieve the entire content from a table and buffer it in memory before dumping it. Buffering in memory can be a problem if you are dumping large tables. To dump tables row by row, use the \fB\-\-quick\fR option (or \fB\-\-opt\fR, which enables \fB\-\-quick\fR). The \fB\-\-opt\fR option (and hence \fB\-\-quick\fR) is enabled by default in MySQL 5.1; to enable memory buffering, use \fB\-\-skip\-quick\fR. .PP If you are using a recent version of \fBmysqldump\fR to generate a dump to be reloaded into a very old MySQL server, you should not use the \fB\-\-opt\fR or \fB\-\-extended\-insert\fR option. Use \fB\-\-skip\-opt\fR instead. .sp .it 1 an-trap .nr an-no-space-flag 1 .nr an-break-flag 1 .br \fBNote\fR .PP \fBmysqldump\fR from the MySQL 5.1.21 distribution cannot be used to create dumps from MySQL server versions 5.1.20 and older. This issue is fixed in MySQL 5.1.22. ([1]\&\fIBug#30123\fR) .PP \fBmysqldump\fR supports the options in the following list. It also reads option files and supports the options for processing them described at Section\ 4.2.3.3.1, \(lqCommand\-Line Options that Affect Option\-File Handling\(rq. .TP 3n \(bu \fB\-\-help\fR, \fB\-?\fR .sp Display a help message and exit. .TP 3n \(bu \fB\-\-add\-drop\-database\fR .sp Add a DROP DATABASE statement before each CREATE DATABASE statement. .TP 3n \(bu \fB\-\-add\-drop\-table\fR .sp Add a DROP TABLE statement before each CREATE TABLE statement. .TP 3n \(bu \fB\-\-add\-locks\fR .sp Surround each table dump with LOCK TABLES and UNLOCK TABLES statements. This results in faster inserts when the dump file is reloaded. See Section\ 7.2.21, \(lqSpeed of INSERT Statements\(rq. .TP 3n \(bu \fB\-\-all\-databases\fR, \fB\-A\fR .sp Dump all tables in all databases. This is the same as using the \fB\-\-databases\fR option and naming all the databases on the command line. .TP 3n \(bu \fB\-\-all\-tablespaces\fR, \fB\-Y\fR .sp Adds to a table dump all SQL statements needed to create any tablespaces used by an NDBCLUSTER table. This information is not otherwise included in the output from \fBmysqldump\fR. This option is currently relevant only to MySQL Cluster tables. .sp This option was added in MySQL 5.1.6. .TP 3n \(bu \fB\-\-allow\-keywords\fR .sp Allow creation of column names that are keywords. This works by prefixing each column name with the table name. .TP 3n \(bu \fB\-\-character\-sets\-dir=\fR\fB\fIpath\fR\fR .sp The directory where character sets are installed. See Section\ 9.2, \(lqThe Character Set Used for Data and Sorting\(rq. .TP 3n \(bu \fB\-\-comments\fR, \fB\-i\fR .sp Write additional information in the dump file such as program version, server version, and host. This option is enabled by default. To suppress this additional information, use \fB\-\-skip\-comments\fR. .TP 3n \(bu \fB\-\-compact\fR .sp Produce less verbose output. This option enables the \fB\-\-skip\-add\-drop\-table\fR, \fB\-\-skip\-add\-locks\fR, \fB\-\-skip\-comments\fR, \fB\-\-skip\-disable\-keys\fR, and \fB\-\-skip\-set\-charset\fR options. .sp .it 1 an-trap .nr an-no-space-flag 1 .nr an-break-flag 1 .br \fBNote\fR Prior to release 5.1.21, this option did not create valid SQL if the database dump contained views. The recreation of views requires the creation and removal of temporary tables and this option suppressed the removal of those temporary tables. As a workaround, use \fB\-\-compact\fR with the \fB\-\-add\-drop\-table\fR option and then manually adjust the dump file. .TP 3n \(bu \fB\-\-compatible=\fR\fB\fIname\fR\fR .sp Produce output that is more compatible with other database systems or with older MySQL servers. The value of name can be ansi, mysql323, mysql40, postgresql, oracle, mssql, db2, maxdb, no_key_options, no_table_options, or no_field_options. To use several values, separate them by commas. These values have the same meaning as the corresponding options for setting the server SQL mode. See Section\ 5.1.8, \(lqServer SQL Modes\(rq. .sp This option does not guarantee compatibility with other servers. It only enables those SQL mode values that are currently available for making dump output more compatible. For example, \fB\-\-compatible=oracle\fR does not map data types to Oracle types or use Oracle comment syntax. .sp \fIThis option requires a server version of 4.1.0 or higher\fR. With older servers, it does nothing. .TP 3n \(bu \fB\-\-complete\-insert\fR, \fB\-c\fR .sp Use complete INSERT statements that include column names. .TP 3n \(bu \fB\-\-compress\fR, \fB\-C\fR .sp Compress all information sent between the client and the server if both support compression. .TP 3n \(bu \fB\-\-create\-options\fR .sp Include all MySQL\-specific table options in the CREATE TABLE statements. .TP 3n \(bu \fB\-\-databases\fR, \fB\-B\fR .sp Dump several databases. Normally, \fBmysqldump\fR treats the first name argument on the command line as a database name and following names as table names. With this option, it treats all name arguments as database names. CREATE DATABASE and USE statements are included in the output before each new database. .TP 3n \(bu \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 \'d:t:o,\fIfile_name\fR'. The default value is \'d:t:o,/tmp/mysqldump.trace'. .TP 3n \(bu \fB\-\-debug\-check\fR .sp Print some debugging information when the program exits. This option was added in MySQL 5.1.21. .TP 3n \(bu \fB\-\-debug\-info\fR .sp Print debugging information and memory and CPU usage statistics when the program exits. This option was added in MySQL 5.1.14. .TP 3n \(bu \fB\-\-default\-character\-set=\fR\fB\fIcharset_name\fR\fR .sp Use \fIcharset_name\fR as the default character set. See Section\ 9.2, \(lqThe Character Set Used for Data and Sorting\(rq. If no character set is specified, \fBmysqldump\fR uses utf8, and earlier versions use latin1. .sp This option has no effect for output data files produced by using the \fB\-\-tab\fR option. See the description for that option. .TP 3n \(bu \fB\-\-delayed\-insert\fR .sp Write INSERT DELAYED statements rather than INSERT statements. .TP 3n \(bu \fB\-\-delete\-master\-logs\fR .sp On a master replication server, delete the binary logs after performing the dump operation. This option automatically enables \fB\-\-master\-data\fR. .TP 3n \(bu \fB\-\-disable\-keys\fR, \fB\-K\fR .sp For each table, surround the INSERT statements with /*!40000 ALTER TABLE \fItbl_name\fR DISABLE KEYS */; and /*!40000 ALTER TABLE \fItbl_name\fR ENABLE KEYS */; statements. This makes loading the dump file faster because the indexes are created after all rows are inserted. This option is effective only for nonunique indexes of MyISAM tables. .TP 3n \(bu \fB\-\-dump\-date\fR .sp \fBmysqldump\fR produces a \-\- Dump completed on \fIDATE\fR comment at the end of the dump if the \fB\-\-comments\fR option is given. However, the date causes dump files for identical data take at different times to appear to be different. \fB\-\-dump\-date\fR and \fB\-\-skip\-dump\-date\fR control whether the date is added to the comment. The default is \fB\-\-dump\-date\fR (include the date in the comment). \fB\-\-skip\-dump\-date\fR suppresses date printing. This option was added in MySQL 5.1.23. .TP 3n \(bu \fB\-\-events\fR, \fB\-E\fR .sp Dump events from the dumped databases. This option was added in MySQL 5.1.8. .TP 3n \(bu \fB\-\-extended\-insert\fR, \fB\-e\fR .sp Use multiple\-row INSERT syntax that include several VALUES lists. This results in a smaller dump file and speeds up inserts when the file is reloaded. .TP 3n \(bu \fB\-\-fields\-terminated\-by=...\fR, \fB\-\-fields\-enclosed\-by=...\fR, \fB\-\-fields\-optionally\-enclosed\-by=...\fR, \fB\-\-fields\-escaped\-by=...\fR .sp These options are used with the \fB\-T\fR option and have the same meaning as the corresponding clauses for LOAD DATA INFILE. See Section\ 12.2.6, \(lqLOAD DATA INFILE Syntax\(rq. .TP 3n \(bu \fB\-\-first\-slave\fR, \fB\-x\fR .sp Deprecated. Now renamed to \fB\-\-lock\-all\-tables\fR. .TP 3n \(bu \fB\-\-flush\-logs\fR, \fB\-F\fR .sp Flush the MySQL server log files before starting the dump. This option requires the RELOAD privilege. Note that if you use this option in combination with the \fB\-\-all\-databases\fR (or \fB\-A\fR) option, the logs are flushed \fIfor each database dumped\fR. The exception is when using \fB\-\-lock\-all\-tables\fR or \fB\-\-master\-data\fR: In this case, the logs are flushed only once, corresponding to the moment that all tables are locked. If you want your dump and the log flush to happen at exactly the same moment, you should use \fB\-\-flush\-logs\fR together with either \fB\-\-lock\-all\-tables\fR or \fB\-\-master\-data\fR. .TP 3n \(bu \fB\-\-flush\-privileges\fR .sp Emit a FLUSH PRIVILEGES statement after dumping the mysql database. This option should be used any time the dump contains the mysql database and any other database that depends on the data in the mysql database for proper restoration. This option was added in MySQL 5.1.12. .TP 3n \(bu \fB\-\-force\fR, \fB\-f\fR .sp Continue even if an SQL error occurs during a table dump. .sp One use for this option is to cause \fBmysqldump\fR to continue executing even when it encounters a view that has become invalid because the definition refers to a table that has been dropped. Without \fB\-\-force\fR, \fBmysqldump\fR exits with an error message. With \fB\-\-force\fR, \fBmysqldump\fR prints the error message, but it also writes an SQL comment containing the view definition to the dump output and continues executing. .TP 3n \(bu \fB\-\-host=\fR\fB\fIhost_name\fR\fR, \fB\-h \fR\fB\fIhost_name\fR\fR .sp Dump data from the MySQL server on the given host. The default host is localhost. .TP 3n \(bu \fB\-\-hex\-blob\fR .sp Dump binary columns using hexadecimal notation (for example, \'abc' becomes 0x616263). The affected data types are BINARY, VARBINARY, BLOB, and BIT. .TP 3n \(bu \fB\-\-ignore\-table=\fR\fB\fIdb_name.tbl_name\fR\fR .sp Do not dump the given table, which must be specified using both the database and table names. To ignore multiple tables, use this option multiple times. This option also can be used to ignore views. .TP 3n \(bu \fB\-\-insert\-ignore\fR .sp Write INSERT statements with the IGNORE option. .TP 3n \(bu \fB\-\-lines\-terminated\-by=...\fR .sp This option is used with the \fB\-T\fR option and has the same meaning as the corresponding clause for LOAD DATA INFILE. See Section\ 12.2.6, \(lqLOAD DATA INFILE Syntax\(rq. .TP 3n \(bu \fB\-\-lock\-all\-tables\fR, \fB\-x\fR .sp Lock all tables across all databases. This is achieved by acquiring a global read lock for the duration of the whole dump. This option automatically turns off \fB\-\-single\-transaction\fR and \fB\-\-lock\-tables\fR. .TP 3n \(bu \fB\-\-lock\-tables\fR, \fB\-l\fR .sp Lock all tables before dumping them. The tables are locked with READ LOCAL to allow concurrent inserts in the case of MyISAM tables. For transactional tables such as InnoDB and BDB, \fB\-\-single\-transaction\fR is a much better option, because it does not need to lock the tables at all. .sp Please note that when dumping multiple databases, \fB\-\-lock\-tables\fR locks tables for each database separately. Therefore, this option does not guarantee that the tables in the dump file are logically consistent between databases. Tables in different databases may be dumped in completely different states. .TP 3n \(bu \fB\-\-log\-error=\fR\fB\fIfile_name\fR\fR .sp Append warnings and errors to the named file. This option was added in MySQL 5.1.18. .TP 3n \(bu \fB\-\-master\-data[=\fR\fB\fIvalue\fR\fR\fB]\fR .sp Use this option to dump a master replication server to produce a dump file that can be used to set up another server as a slave of the master. It causes the dump output to include a CHANGE MASTER TO statement that indicates the binary log coordinates (file name and position) of the dumped server. These are the master server coordinates from which the slave should start replicating. .sp If the option value is 2, the CHANGE MASTER TO statement is written as an SQL comment, and thus is informative only; it has no effect when the dump file is reloaded. If the option value is 1, the statement takes effect when the dump file is reloaded. If the option value is not specified, the default value is 1. .sp This option requires the RELOAD privilege and the binary log must be enabled. .sp The \fB\-\-master\-data\fR option automatically turns off \fB\-\-lock\-tables\fR. It also turns on \fB\-\-lock\-all\-tables\fR, unless \fB\-\-single\-transaction\fR also is specified, in which case, a global read lock is acquired only for a short time at the beginning of the dump (see the description for \fB\-\-single\-transaction\fR). In all cases, any action on logs happens at the exact moment of the dump. .sp It is also possible to set up a slave by dumping an existing slave of the master. To do this, use the following procedure on the existing slave: .RS 3n .TP 3n 1. Stop the slave's SQL thread and get its current status: .sp .RS 3n .nf mysql> \fBSTOP SLAVE SQL_THREAD;\fR mysql> \fBSHOW SLAVE STATUS;\fR .fi .RE .TP 3n 2. From the output of the SHOW SLAVE STATUS statement, get the binary log coordinates of the master server from which the new slave should start replicating. These coordinates are the values of the Relay_Master_Log_File and Exec_Master_Log_Pos values. Denote those values as file_name and file_pos. .TP 3n 3. Dump the slave server: .sp .RS 3n .nf shell> \fBmysqldump \-\-master\-data=2 \-\-all\-databases > dumpfile\fR .fi .RE .TP 3n 4. Restart the slave: .sp .RS 3n .nf mysql> \fBSTART SLAVE;\fR .fi .RE .TP 3n 5. On the new slave, reload the dump file: .sp .RS 3n .nf shell> \fBmysql < dumpfile\fR .fi .RE .TP 3n 6. On the new slave, set the replication coordinates to those of the master server obtained earlier: .sp .RS 3n .nf mysql> \fBCHANGE MASTER TO\fR \-> \fBMASTER_LOG_FILE = 'file_name', MASTER_LOG_POS = file_pos;\fR .fi .RE The CHANGE MASTER TO statement might also need other parameters, such as MASTER_HOST to point the slave to the correct master server host. Add any such parameters as necessary. .RE .TP 3n \(bu \fB\-\-no\-autocommit\fR .sp Enclose the INSERT statements for each dumped table within SET autocommit = 0 and COMMIT statements. .TP 3n \(bu \fB\-\-no\-create\-db\fR, \fB\-n\fR .sp This option suppresses the CREATE DATABASE statements that are otherwise included in the output if the \fB\-\-databases\fR or \fB\-\-all\-databases\fR option is given. .TP 3n \(bu \fB\-\-no\-create\-info\fR, \fB\-t\fR .sp Do not write CREATE TABLE statements that re\-create each dumped table. .TP 3n \(bu \fB\-\-no\-data\fR, \fB\-d\fR .sp Do not write any table row information (that is, do not dump table contents). This is very useful if you want to dump only the CREATE TABLE statement for the table. .TP 3n \(bu \fB\-\-no\-set\-names\fR .sp This option is deprecated. Use \fB\-\-skip\-set\-charset\fR. instead. .TP 3n \(bu \fB\-\-opt\fR .sp This option is shorthand; it is the same as specifying \fB\-\-add\-drop\-table\fR \fB\-\-add\-locks\fR \fB\-\-create\-options\fR \fB\-\-disable\-keys\fR \fB\-\-extended\-insert\fR \fB\-\-lock\-tables\fR \fB\-\-quick\fR \fB\-\-set\-charset\fR. It should give you a fast dump operation and produce a dump file that can be reloaded into a MySQL server quickly. .sp \fIThe \fR\fI\fB\-\-opt\fR\fR\fI option is enabled by default. Use \fR\fI\fB\-\-skip\-opt\fR\fR\fI to disable it.\fR See the discussion at the beginning of this section for information about selectively enabling or disabling certain of the options affected by \fB\-\-opt\fR. .TP 3n \(bu \fB\-\-order\-by\-primary\fR .sp Sorts each table's rows by its primary key, or by its first unique index, if such an index exists. This is useful when dumping a MyISAM table to be loaded into an InnoDB table, but will make the dump itself take considerably longer. .TP 3n \(bu \fB\-\-password[=\fR\fB\fIpassword\fR\fR\fB]\fR, \fB\-p[\fR\fB\fIpassword\fR\fR\fB]\fR .sp The password to use when connecting to the server. If you use the short option form (\fB\-p\fR), you \fIcannot\fR have a space between the option and the password. If you omit the \fIpassword\fR value following the \fB\-\-password\fR or \fB\-p\fR option on the command line, you are prompted for one. .sp Specifying a password on the command line should be considered insecure. See Section\ 5.5.6.2, \(lqEnd\-User Guidelines for Password Security\(rq. .TP 3n \(bu \fB\-\-pipe\fR, \fB\-W\fR .sp On Windows, connect to the server via a named pipe. This option applies only for connections to a local server, and only if the server supports named\-pipe connections. .TP 3n \(bu \fB\-\-port=\fR\fB\fIport_num\fR\fR, \fB\-P \fR\fB\fIport_num\fR\fR .sp The TCP/IP port number to use for the connection. .TP 3n \(bu \fB\-\-protocol={TCP|SOCKET|PIPE|MEMORY}\fR .sp The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the allowable values, see Section\ 4.2.2, \(lqConnecting to the MySQL Server\(rq. .TP 3n \(bu \fB\-\-quick\fR, \fB\-q\fR .sp This option is useful for dumping large tables. It forces \fBmysqldump\fR to retrieve rows for a table from the server a row at a time rather than retrieving the entire row set and buffering it in memory before writing it out. .TP 3n \(bu \fB\-\-quote\-names\fR, \fB\-Q\fR .sp Quote database, table, and column names within \(lq`\(rq characters. If the ANSI_QUOTES SQL mode is enabled, names are quoted within \(lq"\(rq characters. This option is enabled by default. It can be disabled with \fB\-\-skip\-quote\-names\fR, but this option should be given after any option such as \fB\-\-compatible\fR that may enable \fB\-\-quote\-names\fR. .TP 3n \(bu \fB\-\-replace\fR .sp Write REPLACE statements rather than INSERT statements. Available as of MySQL 5.1.3. .TP 3n \(bu \fB\-\-result\-file=\fR\fB\fIfile_name\fR\fR, \fB\-r \fR\fB\fIfile_name\fR\fR .sp Direct output to a given file. This option should be used on Windows to prevent newline \(lq\\n\(rq characters from being converted to \(lq\\r\\n\(rq carriage return/newline sequences. The result file is created and its contents overwritten, even if an error occurs while generating the dump. The previous contents are lost. .TP 3n \(bu \fB\-\-routines\fR, \fB\-R\fR .sp Dump stored routines (procedures and functions) from the dumped databases. Use of this option requires the SELECT privilege for the mysql.proc table. The output generated by using \fB\-\-routines\fR contains CREATE PROCEDURE and CREATE FUNCTION statements to re\-create the routines. However, these statements do not include attributes such as the routine creation and modification timestamps. This means that when the routines are reloaded, they will be created with the timestamps equal to the reload time. .sp If you require routines to be re\-created with their original timestamp attributes, do not use \fB\-\-routines\fR. Instead, dump and reload the contents of the mysql.proc table directly, using a MySQL account that has appropriate privileges for the mysql database. .sp This option was added in MySQL 5.1.2. Before that, stored routines are not dumped. Routine DEFINER values are not dumped until MySQL 5.1.8. This means that before 5.1.8, when routines are reloaded, they will be created with the definer set to the reloading user. If you require routines to be re\-created with their original definer, dump and load the contents of the mysql.proc table directly as described earlier. .TP 3n \(bu \fB\-\-set\-charset\fR .sp Add SET NAMES \fIdefault_character_set\fR to the output. This option is enabled by default. To suppress the SET NAMES statement, use \fB\-\-skip\-set\-charset\fR. .TP 3n \(bu \fB\-\-single\-transaction\fR .sp This option issues a BEGIN SQL statement before dumping data from the server. It is useful only with transactional tables such as InnoDB, because then it dumps the consistent state of the database at the time when BEGIN was issued without blocking any applications. .sp When using this option, you should keep in mind that only InnoDB tables are dumped in a consistent state. For example, any MyISAM or MEMORY tables dumped while using this option may still change state. .sp While a \fB\-\-single\-transaction\fR dump is in process, to ensure a valid dump file (correct table contents and binary log position), no other connection should use the following statements: ALTER TABLE, DROP TABLE, RENAME TABLE, TRUNCATE TABLE. A consistent read is not isolated from those statements, so use of them on a table to be dumped can cause the SELECT performed by \fBmysqldump\fR to retrieve the table contents to obtain incorrect contents or fail. .sp This option is not supported for MySQL Cluster tables; the results cannot be guaranteed to be consistent due to the fact that the NDBCLUSTER storage engine supports only the READ_COMMITTED transaction isolation level. You should always use NDB backup and restore instead. .sp The \fB\-\-single\-transaction\fR option and the \fB\-\-lock\-tables\fR option are mutually exclusive, because LOCK TABLES causes any pending transactions to be committed implicitly. .sp To dump large tables, you should combine this option with \fB\-\-quick\fR. .TP 3n \(bu \fB\-\-skip\-comments\fR .sp See the description for the \fB\-\-comments\fR option. .TP 3n \(bu \fB\-\-skip\-opt\fR .sp See the description for the \fB\-\-opt\fR option. .TP 3n \(bu \fB\-\-socket=\fR\fB\fIpath\fR\fR, \fB\-S \fR\fB\fIpath\fR\fR .sp For connections to localhost, the Unix socket file to use, or, on Windows, the name of the named pipe to use. .TP 3n \(bu \fB\-\-ssl*\fR .sp Options that begin with \fB\-\-ssl\fR specify whether to connect to the server via SSL and indicate where to find SSL keys and certificates. See Section\ 5.5.7.3, \(lqSSL Command Options\(rq. .TP 3n \(bu \fB\-\-tab=\fR\fB\fIpath\fR\fR, \fB\-T \fR\fB\fIpath\fR\fR .sp Produce tab\-separated data files. For each dumped table, \fBmysqldump\fR creates a \fI\fItbl_name\fR\fR\fI.sql\fR file that contains the CREATE TABLE statement that creates the table, and a \fI\fItbl_name\fR\fR\fI.txt\fR file that contains its data. The option value is the directory in which to write the files. .sp By default, the \fI.txt\fR data files are formatted using tab characters between column values and a newline at the end of each line. The format can be specified explicitly using the \fB\-\-fields\-\fR\fB\fIxxx\fR\fR and \fB\-\-lines\-terminated\-by\fR options. .sp Column values are dumped using the binary character set and the \fB\-\-default\-character\-set\fR option is ignored. In effect, there is no character set conversion. If a table contains columns in several character sets, the output data file will as well and you may not be able to reload the file correctly. .sp .it 1 an-trap .nr an-no-space-flag 1 .nr an-break-flag 1 .br \fBNote\fR This option should be used only when \fBmysqldump\fR is run on the same machine as the \fBmysqld\fR server. You must have the FILE privilege, and the server must have permission to write files in the directory that you specify. .TP 3n \(bu \fB\-\-tables\fR .sp Override the \fB\-\-databases\fR or \fB\-B\fR option. \fBmysqldump\fR regards all name arguments following the option as table names. .TP 3n \(bu \fB\-\-triggers\fR .sp Dump triggers for each dumped table. This option is enabled by default; disable it with \fB\-\-skip\-triggers\fR. .TP 3n \(bu \fB\-\-tz\-utc\fR .sp This option enables TIMESTAMP columns to be dumped and reloaded between servers in different time zones. \fBmysqldump\fR sets its connection time zone to UTC and adds SET TIME_ZONE='+00:00' to the dump file. Without this option, TIMESTAMP columns are dumped and reloaded in the time zones local to the source and destination servers, which can cause the values to change. \fB\-\-tz\-utc\fR also protects against changes due to daylight saving time. \fB\-\-tz\-utc\fR is enabled by default. To disable it, use \fB\-\-skip\-tz\-utc\fR. This option was added in MySQL 5.1.2. .TP 3n \(bu \fB\-\-user=\fR\fB\fIuser_name\fR\fR, \fB\-u \fR\fB\fIuser_name\fR\fR .sp The MySQL user name to use when connecting to the server. .TP 3n \(bu \fB\-\-verbose\fR, \fB\-v\fR .sp Verbose mode. Print more information about what the program does. .TP 3n \(bu \fB\-\-version\fR, \fB\-V\fR .sp Display version information and exit. .TP 3n \(bu \fB\-\-where='\fR\fB\fIwhere_condition\fR\fR\fB'\fR, \fB\-w '\fR\fB\fIwhere_condition\fR\fR\fB'\fR .sp Dump only rows selected by the given WHERE condition. Quotes around the condition are mandatory if it contains spaces or other characters that are special to your command interpreter. .sp Examples: .sp .RS 3n .nf \-\-where="user='jimf'" \-w"userid>1" \-w"userid<1" .fi .RE .TP 3n \(bu \fB\-\-xml\fR, \fB\-X\fR .sp Write dump output as well\-formed XML. .sp \fBNULL\fR\fB, \fR\fB'NULL'\fR\fB, and Empty Values\fR: For some column named \fIcolumn_name\fR, the NULL value, an empty string, and the string value \'NULL' are distinguished from one another in the output generated by this option as follows. .TS allbox tab(:); l l l l l l l l. T{ \fBValue\fR: T}:T{ \fBXML Representation\fR: T} T{ NULL (\fIunknown value\fR) T}:T{ T} T{ \'' (\fIempty string\fR) T}:T{ T} T{ \'NULL' (\fIstring value\fR) T}:T{ NULL T} .TE .sp Beginning with MySQL 5.1.12, the output from the \fBmysql\fR client when run using the \fB\-\-xml\fR option also follows these rules. (See the section called \(lq\fBMYSQL\fR OPTIONS\(rq.) .sp Beginning with MySQL 5.1.18, XML output from \fBmysqldump\fR includes the XML namespace, as shown here: .sp .RS 3n .nf shell> \fBmysqldump \-\-xml \-u root world City\fR 1 Kabul AFG Kabol 1780000 \fI...\fR 4079 Rafah PSE Rafah 92020 .fi .RE .sp .sp .RE .PP You can also set the following variables by using \fB\-\-\fR\fB\fIvar_name\fR\fR\fB=\fR\fB\fIvalue\fR\fR syntax: .TP 3n \(bu max_allowed_packet .sp The maximum size of the buffer for client/server communication. The maximum is 1GB. .TP 3n \(bu net_buffer_length .sp The initial size of the buffer for client/server communication. When creating multiple\-row\-insert statements (as with option \fB\-\-extended\-insert\fR or \fB\-\-opt\fR), \fBmysqldump\fR creates rows up to net_buffer_length length. If you increase this variable, you should also ensure that the net_buffer_length variable in the MySQL server is at least this large. .sp .RE .PP The most common use of \fBmysqldump\fR is probably for making a backup of an entire database: .sp .RS 3n .nf shell> \fBmysqldump \fR\fB\fIdb_name\fR\fR\fB > \fR\fB\fIbackup\-file.sql\fR\fR .fi .RE .PP You can read the dump file back into the server like this: .sp .RS 3n .nf shell> \fBmysql \fR\fB\fIdb_name\fR\fR\fB < \fR\fB\fIbackup\-file.sql\fR\fR .fi .RE .PP Or like this: .sp .RS 3n .nf shell> \fBmysql \-e "source \fR\fB\fI/path\-to\-backup/backup\-file.sql\fR\fR\fB" \fR\fB\fIdb_name\fR\fR .fi .RE .PP \fBmysqldump\fR is also very useful for populating databases by copying data from one MySQL server to another: .sp .RS 3n .nf shell> \fBmysqldump \-\-opt \fR\fB\fIdb_name\fR\fR\fB | mysql \-\-host=\fR\fB\fIremote_host\fR\fR\fB \-C \fR\fB\fIdb_name\fR\fR .fi .RE .PP It is possible to dump several databases with one command: .sp .RS 3n .nf shell> \fBmysqldump \-\-databases \fR\fB\fIdb_name1\fR\fR\fB [\fR\fB\fIdb_name2\fR\fR\fB ...] > my_databases.sql\fR .fi .RE .PP To dump all databases, use the \fB\-\-all\-databases\fR option: .sp .RS 3n .nf shell> \fBmysqldump \-\-all\-databases > all_databases.sql\fR .fi .RE .PP For InnoDB tables, \fBmysqldump\fR provides a way of making an online backup: .sp .RS 3n .nf shell> \fBmysqldump \-\-all\-databases \-\-single\-transaction > all_databases.sql\fR .fi .RE .PP This backup acquires a global read lock on all tables (using FLUSH TABLES WITH READ LOCK) at the beginning of the dump. As soon as this lock has been acquired, the binary log coordinates are read and the lock is released. If long updating statements are running when the FLUSH statement is issued, the MySQL server may get stalled until those statements finish. After that, the dump becomes lock\-free and does not disturb reads and writes on the tables. If the update statements that the MySQL server receives are short (in terms of execution time), the initial lock period should not be noticeable, even with many updates. .PP For point\-in\-time recovery (also known as \(lqroll\-forward,\(rq when you need to restore an old backup and replay the changes that happened since that backup), it is often useful to rotate the binary log (see Section\ 5.2.4, \(lqThe Binary Log\(rq) or at least know the binary log coordinates to which the dump corresponds: .sp .RS 3n .nf shell> \fBmysqldump \-\-all\-databases \-\-master\-data=2 > all_databases.sql\fR .fi .RE .PP Or: .sp .RS 3n .nf shell> \fBmysqldump \-\-all\-databases \-\-flush\-logs \-\-master\-data=2\fR \fB> all_databases.sql\fR .fi .RE .PP The \fB\-\-master\-data\fR and \fB\-\-single\-transaction\fR options can be used simultaneously, which provides a convenient way to make an online backup suitable for point\-in\-time recovery if tables are stored using the InnoDB storage engine. .PP For more information on making backups, see Section\ 6.1, \(lqDatabase Backups\(rq, and Section\ 6.2, \(lqExample Backup and Recovery Strategy\(rq. .PP If you encounter problems backing up views, please read the section that covers restrictions on views which describes a workaround for backing up views when this fails due to insufficient privileges. See Section\ D.4, \(lqRestrictions on Views\(rq. .SH "COPYRIGHT" .PP Copyright 2007\-2008 MySQL AB, 2009 Sun Microsystems, Inc. .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/. .SH "REFERENCES" .TP 3 1.\ Bug#30123 \%http://bugs.mysql.com/30123 .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 Sun Microsystems, Inc. (http://www.mysql.com/).