The mysqldump 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 database server (not necessarily MariaDB or MySQL). The dump typically contains SQL statements to create the table, populate it, or both. However, mysqldump can also be used to generate files in CSV, other delimited text, or XML format.

If you are doing a backup on the server and your tables all are MyISAM tables, consider using mysqlhotcopy instead because it can accomplish faster backups and faster restores.

mysqldump dumps triggers along with tables, as these are part of the table definition. However, stored procedures, views, and events are not, and need extra parameters to be recreated explicitly (for example, --routines and --events). Procedures and functions are however also part of the system tables (for example mysql.proc).


mysqldump doesn't usually consume much CPU resources on modern hardware as by default it uses a single thread. This method is good for a heavily loaded server.

Disk input/outputs per second (IOPS), can however increase for multiple reasons. When you back-up on the same device as the database, this produces unnecessary random IOPS. The dump is done sequentially, on a per table basis, causing a full-table scan and many buffer page misses on tables that are not fully cached in memory.

It's recommended that you back-up from a network location to remove disk IOPS on the database server, but it is vital to use a separate network card to keep network bandwidth available for regular traffic.

Although mysqldump will by default preserve your resources for regular spindle disks and low-core hardware, this doesn't mean that concurrent dumps cannot benefit from hardware architecture like SAN, flash storage, low write workload. The back-up time would benefit from a tool such as MyDumper.


There are three general ways to invoke mysqldump:

shell> mysqldump [options] db_name [tbl_name ...]
shell> mysqldump [options] --databases db_name ...
shell> mysqldump [options] --all-databases

If you do not name any tables following db_name or if you use the --databases or --all-databases option, entire databases are dumped.

mysqldump does not dump the INFORMATION_SCHEMA database by default. In all versions of MariaDB and in MySQL 5.1.38 and higher, mysqldump dumps INFORMATION_SCHEMA if you name it explicitly on the command line, although currently you must also use the --skip-lock-tables option. Before MySQL 5.1.38, mysqldump silently ignored INFORMATION_SCHEMA even if you named it explicitly on the command line.

To see a list of the options your version of mysqldump supports, execute mysqldump --help.

Row by row vs. buffering

mysqldump 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 --quick option (or --opt, which enables --quick). The --opt option (and hence --quick) is enabled by default, so to enable memory buffering, use --skip-quick.

mysqldump in MariaDB 10.3 and higher

mysqldump in MariaDB 10.3 includes logic to cater for the mysql.transaction_registry table. mysqldump from an earlier MariaDB release cannot be used on MariaDB 10.3 and beyond.

mysqldump in MariaDB 5.3 and higher

Starting in MariaDB 5.3, mysqldump has been extended to support new enhancements for START TRANSACTION WITH CONSISTENT SNAPSHOT.

mysqldump and old versions of MySQL

If you are using a recent version of mysqldump to generate a dump to be reloaded into a very old MySQL server, you should not use the --opt or --extended-insert option. Use --skip-opt instead.


mysqldump supports the following options:

--allDeprecated. Use --create-options instead.
-A, --all-databasesDump all the databases. This will be same as --databases with all databases selected.
-Y, --all-tablespacesDump all the tablespaces.
-y, --no-tablespacesDo not dump any tablespace information.
--add-drop-databaseAdd a DROP DATABASE before each create. Typically used in conjunction with the --all-databases or --databases option because no CREATE DATABASE statements are written unless one of those options is specified.
--add-drop-tableAdd a DROP TABLE before each create.
--add-drop-triggerAdd a DROP TRIGGER statement before each CREATE TRIGGER. From MariaDB 10.2.6.
--add-locksAdd locks around INSERT statements, which results in faster inserts when the dump file is reloaded. Use --skip-add-locks to disable.
--allow-keywordsAllow creation of column names that are keywords. This works by prefixing each column name with the table name.
--character-sets-dir=nameDirectory for character set files.
-i, --commentsWrite additional information in the dump file such as program version, server version, and host. Disable with --skip-comments.
--compactGive less verbose output (useful for debugging). Disables structure comments and header/footer constructs. Enables the --skip-add-drop-table, --skip-add-locks, --skip-comments, --skip-disable-keys, and --skip-set-charset options.
--compatible=nameChange the dump to be compatible with a given mode. By default tables are dumped in a format optimized for MariaDB and MySQL. Legal modes are: ansi, mysql323, mysql40, postgresql, oracle, mssql, db2, maxdb, no_key_options, no_table_options, and no_field_options. One can use several modes separated by commas.

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, --compatible=oracle does not map data types to Oracle types or use Oracle comment syntax.

-c, --complete-insertUse complete INSERT statements that include column names.
-C, --compressUse compression in server/client protocol. Both client and server must support compression for this to work.
-a, --create-optionsInclude all MariaDB and/or MySQL specific create options in CREATE TABLE statements. Use --skip-create-options to disable.
-B, --databasesDump 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 and USE statements are included in the output before each new database.
-#, --debug[=#]If using a debug version of MariaDB, write a debugging log. A typical debug_options string is ´d:t:o,file_name´. The default value is ´d:t:o,/tmp/mysqldump.trace´. If using a non-debug version, mysqldump will catch this and exit.
--debug-checkCheck memory and open file usage at exit.
--debug-infoPrint some debug info at exit.
--default-auth=nameDefault authentication client-side plugin to use.
--default-character-set=nameSet the default character set to name. If no character set is specified, until MariaDB 10.3.11, mysqldump uses utf8, and from MariaDB 10.3.11, uses utf8mb4.
--defaults-extra-file=nameRead the file name after the global files are read. Must be given as the first argument.
--defaults-file=nameOnly read default options from the given file name. Must be given as the first argument.
--defaults-group-suffix=strAlso read groups with a suffix of str. For example, since mysqldump normally reads the [client] and [mysqldump] groups, --defaults-group-suffix=x would cause it to also read the groups [mysqldump_x] and [client_x].
--delayed-insertInsert rows with INSERT DELAYED instead of INSERT.
--delete-master-logsOn a master replication server, delete the binary logs by sending a PURGE BINARY LOGS statement to the server after performing the dump operation. This option automatically enables --master-data.
-K, --disable-keys'/*!40000 ALTER TABLE tb_name DISABLE KEYS */; and '/*!40000 ALTER TABLE tb_name ENABLE KEYS */; will be put in the output. This makes loading the dump file faster because the indexes are created after all rows are inserted. This option is effective only for non-unique indexes of MyISAM tables. Disable with --skip-disable-keys.
--dump-dateIf the --comments option and this option are given, mysqldump produces a comment at the end of the dump of the following form:
-- Dump completed on DATE
However, the date causes dump files taken at different times to appear to be different, even if the data are otherwise identical. --dump-date and --skip-dump-date control whether the date is added to the comment. The default is --dump-date (include the date in the comment). --skip-dump-date suppresses date printing.
--dump-slave[=value]Used for producing a dump file from a replication slave server that can be used to set up another slave server with the same master. Causes the binary log position and filename of the master to be appended to the dumped data output. Setting the value to 1 (the default) will print it as a CHANGE MASTER command in the dumped data output; if set to 2, that command will be prefixed with a comment symbol. This option will turn --lock-all-tables on, unless --single-transaction is specified too (in which case a global read lock is only taken a short time at the beginning of the dump - don't forget to read about --single-transaction below). In all cases any action on logs will happen at the exact moment of the dump. Option automatically turns --lock-tables off. Using this option causes mysqldump to stop the slave SQL thread before beginning the dump, and restart it again after completion.
-E, --eventsInclude Event Scheduler events for the dumped databases in the output.
-e, --extended-insertUse 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. Defaults to on; use --skip-extended-insert to disable.
--fields-terminated-by=nameFields in the output file are terminated by the given string. Used with the --tab option and has the same meaning as the corresponding FIELDS clause for LOAD DATA INFILE.
--fields-enclosed-by=nameFields in the output file are enclosed by the given character. Used with the --tab option and has the same meaning as the corresponding FIELDS clause for LOAD DATA INFILE.
--fields-optionally-enclosed-by=nameFields in the output file are optionally enclosed by the given character. Used with the --tab option and has the same meaning as the corresponding FIELDS clause for LOAD DATA INFILE.
--fields-escaped-by=nameFields in the output file are escaped by the given character. Used with the --tab option and has the same meaning as the corresponding FIELDS clause for LOAD DATA INFILE.
--first-slaveRemoved in MariaDB 5.5. Use --lock-all-tables instead.
-F, --flush-logsFlush the MariaDB server log files before starting the dump. This option requires the RELOAD privilege. If you use this option in combination with the --databases= or --all-databases option, the logs are flushed for each database dumped. The exception is when using --lock-all-tablesor --master-data: In this case, the logs are flushed only once, corresponding to the moment all tables are locked. If you want your dump and the log flush to happen at the same exact moment, you should use --flush-logs together with either --lock-all-tables or --master-data.
--flush-privilegesSend a FLUSH PRIVILEGES statement to the server 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. Added in MySQL 5.1.12.
-f, --forceContinue even if an SQL error occurs during a table dump.

One use for this option is to cause mysqldump 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 --force in this example, mysqldump exits with an error message. With --force, mysqldump prints the error message, but it also writes an SQL comment containing the view definition to the dump output and continues executing.
--gtidThis option is available from version 10.0.13, and is used together with --master-data and --dump-slave to more conveniently set up a new GTID slave. It causes those options to output SQL statements that configure the slave to use the global transaction ID to connect to the master instead of old-style filename/offset positions. The old-style positions are still included in comments when --gtid is used; likewise the GTID position is included in comments even if --gtid is not used.
-?, --helpDisplay a help message and exit.
--hex-blobDump binary strings in hexadecimal format (for example, ´abc´ becomes 0x616263). The affected data types are BINARY, VARBINARY, the BLOB types, and BIT.
-h name, --host=nameConnect to and dump data from the MariaDB or MySQL server on the given host. The default host is localhost.
--ignore-table=nameDo not dump the specified table. To specify more than one table to ignore, use the directive multiple times, once for each table. Each table must be specified with both database and table names, e.g., --ignore-table=database.table. This option also can be used to ignore views.
--include-master-host-portAdd the MASTER_HOST and MASTER_PORT options for the CHANGE MASTER TO statement when using the --dump-slave option for a slave dump.
--insert-ignoreInsert rows with INSERT IGNORE instead of INSERT.
--lines-terminated-by=nameLines in the output file are terminated by the given string. This option is used with the --tab option and has the same meaning as the corresponding LINES clause for LOAD DATA INFILE.
-x, --lock-all-tablesLock all tables across all databases. This is achieved by acquiring a global read lock for the duration of the whole dump by executing FLUSH TABLES WITH READ LOCK. This option automatically turns off --single-transaction and --lock-tables.
-l, --lock-tablesFor each dumped database, lock all tables to be dumped 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, --single-transaction is a much better option than --lock-tables because it does not need to lock the tables at all.

Because --lock-tables locks tables for each database separately, 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. Use --skip-lock-tables to disable.
--log-error=nameLog warnings and errors by appending them to the named file. The default is to do no logging.
--log-queriesWhen restoring the dump, the server will, if logging is turned on, log the queries to the general and slow query log. Defaults to on; use --skip-log-queries to disable. Added in MariaDB 10.1.1.
--master-data[=#]Causes the binary log position and filename to be appended to the output, useful for dumping a master replication server to produce a dump file that can be used to set up another server as a slave of the master. These are the master server coordinates from which the slave should start replicating after you load the dump file into the slave. If the option is set to 1 (the default), will print it as a CHANGE MASTER command; if set to 2, that command will be prefixed with a comment symbol. This --master-data option will turn --lock-all-tables on, unless --single-transaction is specified too. Before MariaDB 5.3 this would take a global read lock for a short time at the beginning of the dump - see Enhancements for START TRANSACTION WITH CONSISTENT SNAPSHOT and the --single-transaction option below). In all cases, any action on logs will happen at the exact moment of the dump. This option automatically turns --lock-tables off.

In all cases, any action on logs happens at the exact moment of the dump.

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:

1. Stop the slave´s SQL thread and get its current status:

2. From the output of the SHOW SLAVE STATUS statement, the binary log coordinates of the master server from which the new slave should start replicating are the values of the Relay_Master_Log_File and Exec_Master_Log_Pos fields. Denote those values as file_name and file_pos.

2. Dump the slave server:
shell> mysqldump --master-data=2 --all-databases > dumpfile

3. Restart the slave:

4. On the new slave, load the dump file:
shell> mysql < dumpfile

5. On the new slave, set the replication coordinates to those of the master server obtained earlier:
mysql> CHANGE MASTER TO MASTER_LOG_FILE = ´file_name´, MASTER_LOG_POS = file_pos;
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.
--max-allowed-packet=# The maximum packet length to send to or receive from server.
--net-buffer-length=# The buffer size for TCP/IP and socket communication.
--no-autocommitEnclose the INSERT statements for each dumped table within SET autocommit = 0 and COMMIT statements.
-n, --no-create-dbThis option suppresses the CREATE DATABASE ... IF EXISTS statement that normally is output for each dumped database if --all-databases or --databases is given.
-t, --no-create-infoDo not write CREATE TABLE statements which re-create each dumped table.
-d, --no-dataDo not write any table row information (that is, do not dump table contents). This is useful if you want to dump only the CREATE TABLE statement for the table (for example, to create an empty copy of the table by loading the dump file).
--no-defaultsDon't read default options from any option file. Must be given as the first argument.
-N, --no-set-namesSuppress the SET NAMES statement. This has the same effect as --skip-set-charset.
--optThis option is shorthand. It is the same as specifying --add-drop-table, --add-locks, --create-options, --quick, --extended-insert, --lock-tables, --set-charset, and --disable-keys. Enabled by default, disable with --skip-opt. It should give you a fast dump operation and produce a dump file that can be reloaded into a MariaDB server quickly.

The --opt option is enabled by default. Use --skip-opt to disable it. See the discussion at the beginning of this section for information about selectively enabling or disabling a subset of the options affected by --opt.
--order-by-primarySorts each table's rows by primary key, or first unique key, if such a key 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.
-p[passwd], --password[=passwdThe 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, mysqldump prompts for one.

Specifying a password on the command line should be considered insecure. You can use an option file to avoid giving the password on the command line.
-W, --pipeOn Windows, connect to the server via a named pipe. This option applies only if the server supports named-pipe connections.
--plugin-dirDirectory for client-side plugins.
-P num, --port=numThe TCP/IP port number to use for the connection.
--print-defaultsPrint the program argument list and exit. Must be given as the first argument.
--protocol=nameThe connection protocol to use for connecting to the server (TCP, SOCKET, PIPE, MEMORY). It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want.
-q, --quickThis option is useful for dumping large tables. It forces mysqldump to retrieve rows for a table from the server a row at a time and to then dump the results directly to stdout rather than retrieving the entire row set and buffering it in memory before writing it out. Defaults to on, use --skip-quick to disable.
-Q, --quote-namesQuote identifiers (such as database, table, and column names) within backtick (`) characters. If the ANSI_QUOTES SQL mode is enabled, identifiers are quoted within (") characters. This option is enabled by default. It can be disabled with --skip-quote-names, but this option should be given after any option such as --compatible that may enable --quote-names.
--replaceUse REPLACE INTO statements instead of INSERT INTO statements. Added in MySQL 5.1.3.
-r, --result-file=nameDirect output to a given file. This option should be used on Windows to prevent newline "\n" characters from being converted to "\r\n" carriage return/newline sequences. The result file is created and its previous contents overwritten, even if an error occurs while generating the dump.
-R, --routinesInclude stored routines (procedures and functions) for the dumped databases in the output. Use of this option requires the SELECT privilege for the mysql.proc table. The output generated using --routines 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.

If you require routines to be re-created with their original timestamp attributes, do not use --routines. Instead, dump and reload the contents of the mysql.proc table directly, using a MariaDB account which has appropriate privileges for the mysql database.

Added in MySQL 5.1.2.
set-charsetAdd 'SET NAMES default_character_set' to the output in order to set the character set. Enabled by default; suppress with --skip-set-charset.
-O, --set-variable=nameChange the value of a variable. Please note that this option is deprecated; you can set variables directly with --variable-name=value.
--shared-memory-base-nameShared-memory name to use for Windows connections using shared memory to a local server (started with the --shared-memory option). Case-sensitive. Defaults to MYSQL.
--single-transactionThis option sends a START TRANSACTION SQL statement to the server before dumping data. 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.

When using this option, you should keep in mind that only InnoDB tables are dumped in a consistent state. The single-transaction feature depends not only on the engine being transactional and capable of REPEATABLE-READ, but also on START TRANSACTION WITH CONSISTENT SNAPSHOT. The dump is not guaranteed to be consistent for other storage engines. For example, any TokuDB, MyISAM or MEMORY tables dumped while using this option may still change state.

While a --single-transaction dump is in process, to ensure a valid dump file (correct table contents and binary log coordinates), no other connection should use the following statements: ALTER TABLE, CREATE TABLE, DROP TABLE, RENAME TABLE, or 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 mysqldump to retrieve the table contents) to obtain incorrect contents or fail.

The --single-transaction option and the --lock-tables option are mutually exclusive because LOCK TABLES causes any pending transactions to be committed implicitly. So this option automatically turns off --lock-tables

To dump large tables, you should combine the --single-transaction option with --quick.
--skip-add-locksDisable the --add-locks option.
--skip-commentsDisable the --comments option.
--skip-disable-keysDisable the --disable-keys option.
--skip-extended-insertDisable the --extended-insert option.
--skip-optDisable the --opt option (disables --add-drop-table, --add-locks, --create-options, --quick, --extended-insert, --lock-tables, --set-charset, and --disable-keys).
--skip-quickDisable the --quick option.
--skip-quote-nameDisable the --quote-names option.
--skip-set-charsetDisable the --set-charset option.
--skip-triggersDisable the --triggers option.
--skip-tz-utcDisable the --tz-utc option.
-S name, --socket=nameFor connections to localhost, the Unix socket file to use, or, on Windows, the name of the named pipe to use.
--sslEnable TLS for secure connection (automatically enabled with other flags).Disable with '--skip-ssl'.
--ssl-ca=nameCA file in PEM format (check OpenSSL docs, implies --ssl).
--ssl-capath=nameCA directory (check OpenSSL docs, implies --ssl).
--ssl-cert=nameX509 cert in PEM format (implies --ssl).
--ssl-cipher=nameSSL cipher to use (implies --ssl).
--ssl-key=nameX509 key in PEM format (implies --ssl).
--ssl-crl=nameCertificate revocation list (implies --ssl).
--ssl-crlpath=nameCertificate revocation list path (implies --ssl).
--ssl-verify-server-certVerify server's "Common Name" in its cert against hostname used when connecting. This option is disabled by default.
-T, --tab=nameProduce tab-separated text-format data files. With this option, for each dumped table mysqldump will create a tbl_name.sql file containing the CREATE TABLE statement that creates the table, and and a tbl_name.txt file containing the table's data. The option value is the directory in which to write the files.

Note: This option can only be used 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.

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-terminated-by options.

Column values are converted to the character set specified by the --default-character-set option.
--tablesThis option overrides the --databases (-B) option. mysqldump regards all name arguments following the option as table names.
--triggersInclude triggers for each dumped table in the output. This option is enabled by default; disable it with --skip-triggers.
--tz-utcThis option enables TIMESTAMP columns to be dumped and reloaded between servers in different time zones. mysqldump 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 if the servers are in different time zones. --tz-utc also protects against changes due to daylight saving time. --tz-utc is enabled by default. To disable it, use --skip-tz-utc. Added in MySQL 5.1.2.
-u name, --user=nameThe MariaDB user name to use when connecting to the server.
-v, --verboseVerbose mode. Print more information about what the program is doing during various stages.
-V, --versionOutput version information and exit.
-w cond, --where=condDump only rows selected by the given WHERE condition cond. Quotes around the condition are mandatory if it contains spaces or other characters that are special to your command interpreter.

-X, --xmlDump a database as well formed XML.

Group Options

Some mysqldump options are shorthand for groups of other options:

  • Use of --opt is the same as specifying --add-drop-table, --add-locks, --create-options, --disable-keys, --extended-insert, --lock-tables, --quick, and --set-charset. All of the options that --opt stands for also are on by default because --opt is on by default.
  • Use of --compact is the same as specifying --skip-add-drop-table, --skip-add-locks, --skip-comments, --skip-disable-keys, and --skip-set-charset options.

To reverse the effect of a group option, uses its --skip-xxx form (--skip-opt or --skip-compact). 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:

  • To select the effect of --opt except for some features, use the --skip option for each feature. To disable extended inserts and memory buffering, use --opt --skip-extended-insert --skip-quick. (Actually, --skip-extended-insert --skip-quick is sufficient because --opt is on by default.)
  • To reverse --opt for all features except index disabling and table locking, use --skip-opt --disable-keys --lock-tables.

When you selectively enable or disable the effect of a group option, order is important because options are processed first to last. For example, --disable-keys --lock-tables --skip-opt would not have the intended effect; it is the same as --skip-opt by itself.

Special Characters in Option Values

Some options, like --lines-terminated-by, accept a string. The string can be quoted, if necessary. For example, on Unix systems this is the option to enclose fields within double quotes:


An alternative to specify the hexadecimal value of a character. For example, the following syntax works on any platform:


Option Files

In addition to reading options from the command-line, mysqldump can also read options from option files. If an unknown option is provided to mysqldump in an option file, then it is ignored.

The following options relate to how MariaDB command-line tools handles option files. They must be given as the first argument on the command-line:

--print-defaultsPrint the program argument list and exit.
--no-defaultsDon't read default options from any option file.
--defaults-file=# Only read default options from the given file #.
--defaults-extra-file=# Read this file after the global files are read.
--defaults-group-suffix=# In addition to the default option groups, also read option groups with this suffix.

In MariaDB 10.2 and later, mysqldump is linked with MariaDB Connector/C. However, MariaDB Connector/C does not yet handle the parsing of option files for this client. That is still performed by the server option file parsing code. See MDEV-19035 for more information.

Option Groups

mysqldump reads options from the following option groups from option files:

[mysqldump] Options read by mysqldump, which includes both MariaDB Server and MySQL Server.
[client] Options read by all MariaDB and MySQL client programs, which includes both MariaDB and MySQL clients. For example, mysqldump.
[client-server]Options read by all MariaDB client programs and the MariaDB Server. This is useful for options like socket and port, which is common between the server and the clients.
[client-mariadb]Options read by all MariaDB client programs.

NULL, ´NULL´, and empty values in XML

For a column named column_name, 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.

ValueXML Representation
NULL (unknown value)<field name="column_name" xsi:nil="true" />
´´ (empty string)<field name="column_name"></field>
´NULL´ (string value)<field name="column_name">NULL</field>

The output from the mysql client when run using the --xml option also follows the preceding rules.

XML output from mysqldump includes the XML namespace, as shown here :

shell> mysqldump --xml -u root world City
<?xml version="1.0"?>
<mysqldump xmlns:xsi="">
<database name="world">
<table_structure name="City">
<field Field="ID" Type="int(11)" Null="NO" Key="PRI" Extra="auto_increment" />
<field Field="Name" Type="char(35)" Null="NO" Key="" Default="" Extra="" />
<field Field="CountryCode" Type="char(3)" Null="NO" Key="" Default="" Extra="" />
<field Field="District" Type="char(20)" Null="NO" Key="" Default="" Extra="" />
<field Field="Population" Type="int(11)" Null="NO" Key="" Default="0" Extra="" />
<key Table="City" Non_unique="0" Key_name="PRIMARY" Seq_in_index="1" Column_name="ID"
Collation="A" Cardinality="4079" Null="" Index_type="BTREE" Comment="" />
<options Name="City" Engine="MyISAM" Version="10" Row_format="Fixed" Rows="4079"
Avg_row_length="67" Data_length="273293" Max_data_length="18858823439613951"
Index_length="43008" Data_free="0" Auto_increment="4080"
Create_time="2007-03-31 01:47:01" Update_time="2007-03-31 01:47:02"
Collation="latin1_swedish_ci" Create_options="" Comment="" />
<table_data name="City">
<field name="ID">1</field>
<field name="Name">Kabul</field>
<field name="CountryCode">AFG</field>
<field name="District">Kabol</field>
<field name="Population">1780000</field>
<field name="ID">4079</field>
<field name="Name">Rafah</field>
<field name="CountryCode">PSE</field>
<field name="District">Rafah</field>
<field name="Population">92020</field>


To restore a backup created with mysqldump, use the mysql client to import the dump, for example:

mysql db_name < backup-file.sql


You can also set the following variables (--variable-name=value) and boolean options {FALSE|TRUE} by using:

NameDefault ValuesDescription
character-sets-dir(No default value)
compatible(No default value)
default-character-setutf8mb4utf8 until MariaDB 10.3.11
fields-terminated-by(No default value)
fields-enclosed-by(No default value)
fields-optionally-enclosed-by(No default value)
fields-escaped-by(No default value)
host(No default value)
lines-terminated-by(No default value)
log-error(No default value)
max_allowed_packet25165824The maximum size of the buffer for client/server communication. The maximum is 1GB.
net_buffer_length1046528The initial size of the buffer for client/server communication. When creating multiple-row INSERT statements (as with the --extended-insert or --opt option), 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 MariaDB server is at least this large.
socketNo default value)
ssl-ca(No default value)
ssl-capath(No default value)
ssl-cert(No default value)
ssl-cipher(No default value)
ssl-key(No default value)
tab(No default value)
user(No default value)
where(No default value)


A common use of mysqldump is for making a backup of an entire database:

shell> mysqldump db_name > backup-file.sql

You can load the dump file back into the server like this:

shell> mysql db_name < backup-file.sql

Or like this:

shell> mysql -e "source /path-to-backup/backup-file.sql" db_name

mysqldump is also very useful for populating databases by copying data from one MariaDB server to another:

shell> mysqldump --opt db_name | mysql --host=remote_host -C db_name

It is possible to dump several databases with one command:

shell> mysqldump --databases db_name1 [db_name2 ...] > my_databases.sql

To dump all databases, use the --all-databases option:

shell> mysqldump --all-databases > all_databases.sql

For InnoDB tables, mysqldump provides a way of making an online backup:

shell> mysqldump --all-databases --single-transaction all_databases.sql

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 MariaDB 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 MariaDB server receives are short (in terms of execution time), the initial lock period should not be noticeable, even with many updates.

For point-in-time recovery (also known as “roll-forward,” 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, “The Binary Log”) or at least know the binary log coordinates to which the dump corresponds:

shell> mysqldump --all-databases --master-data=2 > all_databases.sql


shell> mysqldump --all-databases --flush-logs --master-data=2 > all_databases.sql

The --master-data and --single-transaction options can be used simultaneously, which provides a convenient way to make an online backup suitable for use prior to point-in-time recovery if tables are stored using the InnoDB storage engine.

See Also

  • mariabackup for physical online backups. Faster and safer than mysqldump, but can only restored on another MariaDB server.


Comments loading...