MySQL Reference Manual :: 8.8 The mysqldump Database Backup Program

--help, -?

Display a help message and exit.

--add-drop-table

Add a DROP TABLE statement before each CREATE TABLE statement.

--add-locks

Surround each table dump with LOCK TABLES and UNLOCK TABLES statements. This results in faster inserts when the dump file is reloaded. See Section 7.2.14, “Speed of INSERT Statements”.

--all-databases, -A

Dump all tables in all databases. This is the same as using the --databases option and naming all the databases on the command line.

--allow-keywords

Allow creation of column names that are keywords. This works by prefixing each column name with the table name.

--comments[={0|1}]

If set to 0, suppresses additional information in the dump file such as program version, server version, and host. --skip-comments has the same effect as --comments=0. The default value is 1 to not suppress the extra information. New in MySQL 4.0.17.

--compact

Produce less verbose output. This option suppresses comments and enables the --skip-add-drop-table, --no-set-names, --skip-disable-keys, and --skip-add-locks options. New in MySQL 4.1.2.

--compatible=name

Produce output that is 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 5.3.2, “The Server SQL Mode”.

This option requires a server version of 4.1.0 or higher. With older servers, it does nothing.

--complete-insert, -c

Use complete INSERT statements that include column names.

--compress, -C

Compress all information sent between the client and the server if both support compression.

--create-options

Include all MySQL-specific table options in the CREATE TABLE statements. Before MySQL 4.1.2, use --all instead.

--databases, -B

Dump several databases. Normally, mysqldump 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 IF NOT EXISTS db_name and USE db_name statements are included in the output before each new database.

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

Write a debugging log. The debug_options string often is 'd:t:o,file_name'.

--default-character-set=charset

Use charset as the default character set. See Section 5.9.1, “The Character Set Used for Data and Sorting”. If not specified, mysqldump from MySQL 4.1.2 or later uses utf8, and earlier versions use latin1.

--delayed-insert

Insert rows using INSERT DELAYED statements. This option was disabled in MySQL 5.0.7.

--delete-master-logs

On a master replication server, delete the binary logs after performing the dump operation. This option automatically enables --first-slave before MySQL 4.1.8 and enables --master-data thereafter. It was added in MySQL 3.23.57 (for MySQL 3.23) and MySQL 4.0.13 (for MySQL 4.0).

--disable-keys, -K

For each table, surround the INSERT statements with /*!40000 ALTER TABLE tbl_name DISABLE KEYS */; and /*!40000 ALTER TABLE tbl_name ENABLE KEYS */; statements. This makes loading the dump file into a MySQL 4.0 server faster because the indexes are created after all rows are inserted. This option is effective only for MyISAM tables.

--extended-insert, -e

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.

--fields-terminated-by=... , --fields-enclosed-by=... , --fields-optionally-enclosed-by=... , --fields-escaped-by=... , --lines-terminated-by=...

These options are used with the -T option and have the same meaning as the corresponding clauses for LOAD DATA INFILE. See Section 13.2.5, “LOAD DATA INFILE Syntax”.

--first-slave, -x

Deprecated, renamed to --lock-all-tables in MySQL 4.1.8.

--flush-logs, -F

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 --all-databases (or -A) option, the logs are flushed for each database dumped. The exception is when using --lock-all-tables or --master-data: 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 --flush-logs together with either --lock-all-tables or --master-data.

--force, -f

Continue even if an SQL error occurs during a table dump.

--host=host_name, -h host_name

Dump data from the MySQL server on the given host. The default host is localhost.

--hex-blob

Dump binary string columns using hexadecimal notation (for example, 'abc' becomes 0x616263). The affected columns are BINARY, VARBINARY, and BLOB in MySQL 4.1 and up, and CHAR BINARY, VARCHAR BINARY, and BLOB in MySQL 4.0. This option was added in MySQL 4.0.23 and 4.1.8.

--lock-all-tables, -x

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 --single-transaction and --lock-tables. Added in MySQL 4.1.8.

--lock-tables, -l

Lock all tables before starting the dump. 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, --single-transaction is a much better option, because it does not need to lock the tables at all.

Please note that when dumping multiple databases, --lock-tables locks tables for each database separately. So, 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.

--master-data[=value]

This option causes the binary log position and filename to be written to the output. This option requires the RELOAD privilege. If the option value is equal to 1, the position and filename are written to the dump output in the form of a CHANGE MASTER statement that makes a slave server start from the correct position in the master's binary logs if you use this SQL dump of the master to set up a slave. If the option value is equal to 2, the CHANGE MASTER statement is written as an SQL comment. This is the default action if value is omitted. value may be given as of MySQL 4.1.8; before that, do not specify an option value.

The --master-data option turns on --lock-all-tables, unless --single-transaction also is specified (in which case, a global read lock is only acquired a short time at the beginning of the dump. See also the description for --single-transaction. In all cases, any action on logs happens at the exact moment of the dump. This option automatically turns off --lock-tables.

--no-create-db, -n

This option suppresses the CREATE DATABASE /*!32312 IF NOT EXISTS*/ db_name statements that are otherwise included in the output if the --databases or --all-databases option is given.

--no-create-info, -t

Don't write CREATE TABLE statements that re-create each dumped table.

--no-data, -d

Don't write any row information for the table. This is very useful if you just want to get a dump of the structure for a table.

--opt

This option is shorthand; it is the same as specifying --add-drop-table --add-locks --create-options --disable-keys --extended-insert --lock-tables --quick --set-charset. It should give you a fast dump operation and produce a dump file that can be reloaded into a MySQL server quickly. As of MySQL 4.1, --opt is on by default, but can be disabled with --skip-opt. To disable only certain of the options enabled by --opt, use their --skip forms; for example, --skip-add-drop-table or --skip-quick.

--password[=password], -p[password]

The password to use when connecting to the server. If you use the short option form (-p), you cannot have a space between the option and the password. If you omit the password value following the --password or -p option on the command line, you are prompted for one.

--port=port_num, -P port_num

The TCP/IP port number to use for the connection.

--protocol={TCP | SOCKET | PIPE | MEMORY}

The connection protocol to use. New in MySQL 4.1.

--quick, -q

This option is useful for dumping large tables. It forces mysqldump 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.

--quote-names, -Q

Quote database, table, and column names within '`' characters. If the server SQL mode includes the ANSI_QUOTES option, names are quoted within '"' characters. As of MySQL 4.1.1, --quote-names is on by default, but can be disabled with --skip-quote-names.

--result-file=file, -r file

Direct output to a given file. This option should be used on Windows, because it prevents newline '\n' characters from being converted to '\r\n' carriage return/newline sequences.

--set-charset

Add SET NAMES default_character_set to the output. This option is enabled by default. To suppress the SET NAMES statement, use --skip-set-charset. This option was added in MySQL 4.1.2.

--single-transaction

This option issues a BEGIN SQL statement before dumping data from the server. It is useful only with transactional tables such as InnoDB and BDB, because then it dumps the consistent state of the database at the time when BEGIN was issued without blocking any applications.

When using this option, you should keep in mind that only InnoDB tables are dumped in a consistent state. For example, any MyISAM or HEAP tables dumped while using this option may still change state.

The --single-transaction option was added in MySQL 4.0.2. This option is mutually exclusive with the --lock-tables option, because LOCK TABLES causes any pending transactions to be committed implicitly.

To dump big tables, you should combine this option with --quick.

--socket=path, -S path

The socket file to use when connecting to localhost (which is the default host).

--skip-comments

See the description for the --comments option.

--tab=path, -T path

Produce tab-separated data files. For each dumped table, mysqldump creates a tbl_name.sql file that contains the CREATE TABLE statement that creates the table, and a tbl_name.txt file that contains its data. The option value is the directory in which to write the files.

By default, the .txt 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 --fields-xxx and --lines--xxx options.

Note: This option should be used only when mysqldump is run on the same machine as the mysqld server. You must have the FILE privilege, and the server must have permission to write files in the directory that you specify.

--tables

Override the --databases or -B option. All arguments following the option are regarded as table names.

--user=user_name, -u user_name

The MySQL username to use when connecting to the server.

--verbose, -v

Verbose mode. Print out more information on what the program does.

--version, -V

Display version information and exit.

--where='where-condition', -w 'where-condition'

Dump only records selected by the given WHERE condition. Note that quotes around the condition are mandatory if it contains spaces or characters that are special to your command interpreter.

Examples:

"--where=user='jimf'"
"-wuserid>1"
"-wuserid<1"

--xml, -X

Write dump output as well-formed XML.

max_allowed_packet

The maximum size of the buffer for client/server communication. The value of the variable can be up to 16MB before MySQL 4.0, and up to 1GB from MySQL 4.0 on.

net_buffer_length

The initial size of the buffer for client/server communication. When creating multiple-row-insert statements (as with option --extended-insert or --opt), mysqldump 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.