MYSQLDUMP(1)                 MySQL Database System                MYSQLDUMP(1)



NAME
       mysqldump - a database backup program

SYNOPSIS
       mysqldump [options] [db_name [tbl_name ...]]

DESCRIPTION
       ·   Performance and Scalability Considerations

       ·   Invocation Syntax

       ·   Option Syntax - Alphabetical Summary

       The mysqldump client utility performs logical backups, producing a set
       of SQL statements that can be executed to reproduce the original
       database object definitions and table data. It dumps one or more MySQL
       databases for backup or transfer to another SQL server. The mysqldump
       command can also generate output in CSV, other delimited text, or XML
       format.

       mysqldump requires at least the SELECT privilege for dumped tables,
       SHOW VIEW for dumped views, TRIGGER for dumped triggers, and LOCK
       TABLES if the --single-transaction option is not used. Certain options
       might require other privileges as noted in the option descriptions.

       To reload a dump file, you must have the privileges required to execute
       the statements that it contains, such as the appropriate CREATE
       privileges for objects created by those statements.

       mysqldump output can include ALTER DATABASE statements that change the
       database collation. These may be used when dumping stored programs to
       preserve their character encodings. To reload a dump file containing
       such statements, the ALTER privilege for the affected database is
       required.

       If you are performing a backup on the server and your tables all are
       MyISAM tables, you can also use mysqlhotcopy for this purpose.

           Note
           A dump made using PowerShell on Windows with output redirection
           creates a file that has UTF-16 encoding:

               shell> mysqldump [options] > dump.sql

           However, UTF-16 is not permitted as a connection character set (see
           Section 10.4, “Connection Character Sets and Collations”), so the
           dump file will not load correctly. To work around this issue, use
           the --result-file option, which creates the output in ASCII format:

               shell> mysqldump [options] --result-file=dump.sql
       Performance and Scalability Considerations.PP mysqldump advantages
       include the convenience and flexibility of viewing or even editing the
       output before restoring. You can clone databases for development and
       DBA work, or produce slight variations of an existing database for
       testing. It is not intended as a fast or scalable solution for backing
       up substantial amounts of data. With large data sizes, even if the
       backup step takes a reasonable time, restoring the data can be very
       slow because replaying the SQL statements involves disk I/O for
       insertion, index creation, and so on.

       For large-scale backup and restore, a physical backup is more
       appropriate, to copy the data files in their original format that can
       be restored quickly:

       ·   If your tables are primarily InnoDB tables, or if you have a mix of
           InnoDB and MyISAM tables, consider using the mysqlbackup command of
           the MySQL Enterprise Backup product. (Available as part of the
           Enterprise subscription.) It provides the best performance for
           InnoDB backups with minimal disruption; it can also back up tables
           from MyISAM and other storage engines; and it provides a number of
           convenient options to accommodate different backup scenarios. See
           Section 25.2, “MySQL Enterprise Backup Overview”.

       ·   If your tables are primarily MyISAM tables, consider using the
           mysqlhotcopy instead, for better performance than mysqldump of
           backup and restore operations. See mysqlhotcopy(1).

       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.

       If you are using a recent version of mysqldump to generate a dump to be
       reloaded into a very old MySQL server, use the --skip-opt option
       instead of the --opt or --extended-insert option.

       For additional information about mysqldump, see Section 7.4, “Using
       mysqldump for Backups”.  Invocation Syntax.PP There are in general
       three ways to use mysqldump—in order to dump a set of one or more
       tables, a set of one or more complete databases, or an entire MySQL
       server—as shown here:

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

       To dump entire databases, do not name any tables following db_name, or
       use the --databases or --all-databases option.

       mysqldump does not dump the INFORMATION_SCHEMA or performance_schema
       database by default. To dump either of these, name it explicitly on the
       command line and also use the --skip-lock-tables option. You can also
       name them with the --databases option. Before MySQL 5.5 mysqldump
       silently ignores INFORMATION_SCHEMA even if you name it explicitly on
       the command line.

       mysqldump does not dump the performance_schema database.

       Before MySQL 5.5.25, mysqldump does not dump the general_log or
       slow_query_log tables for dumps of the mysql database. As of 5.5.25,
       the dump includes statements to recreate those tables so that they are
       not missing after reloading the dump file. Log table contents are not
       dumped.

       mysqldump also does not dump the NDB Cluster ndbinfo information
       database.

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

       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.

       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.

       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.

       For additional information about mysqldump, see Section 7.4, “Using
       mysqldump for Backups”.  Option Syntax - Alphabetical Summary.PP
       mysqldump supports the following options, which can be specified on the
       command line or in the [mysqldump] and [client] groups of an option
       file. For information about option files used by MySQL programs, see
       Section 4.2.6, “Using Option Files”.

       ·   --help, -?

           Display a help message and exit.

       ·   --add-drop-database

           Write a DROP DATABASE statement before each CREATE DATABASE
           statement. This option is 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-table

           Write a DROP TABLE statement before each CREATE TABLE statement.

       ·   --add-drop-trigger

           Write a DROP TRIGGER statement before each CREATE TRIGGER
           statement.

               Note
               This option is supported only by mysqldump as supplied with NDB
               Cluster. It is not available when using MySQL Server 5.5.

       ·   --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 8.2.4.1, “Optimizing 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.

       ·   --all-tablespaces, -Y

           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 mysqldump. This option is
           currently relevant only to NDB Cluster tables.

       ·   --allow-keywords

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

       ·   --apply-slave-statements

           For a slave dump produced with the --dump-slave option, add a STOP
           SLAVE statement before the CHANGE MASTER TO statement and a START
           SLAVE statement at the end of the output. This option was added in
           MySQL 5.5.3.

       ·   --bind-address=ip_address

           On a computer having multiple network interfaces, use this option
           to select which interface to use for connecting to the MySQL
           server.

           This option is supported only in the version of mysqldump that is
           supplied with NDB Cluster. It is not available in standard MySQL
           Server 5.5 releases.

       ·   --character-sets-dir=dir_name

           The directory where character sets are installed. See
           Section 10.14, “Character Set Configuration”.

       ·   --comments, -i

           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
           --skip-comments.

       ·   --compact

           Produce more compact output. This option enables the
           --skip-add-drop-table, --skip-add-locks, --skip-comments,
           --skip-disable-keys, and --skip-set-charset options.

       ·   --compatible=name

           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, “Server SQL Modes”.

           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.

           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.

       ·   --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 and USE statements are included in
           the output before each new database.

           This option may be used to dump the INFORMATION_SCHEMA and
           performace_schema databases, which normally are not dumped even
           with the --all-databases option. (Also use the --skip-lock-tables
           option.)

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

           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.

       ·   --debug-check

           Print some debugging information when the program exits.

       ·   --debug-info

           Print debugging information and memory and CPU usage statistics
           when the program exits.

       ·   --default-auth=plugin

           A hint about the client-side authentication plugin to use. See
           Section 6.3.6, “Pluggable Authentication”.

           This option was added in MySQL 5.5.9.

       ·   --default-character-set=charset_name

           Use charset_name as the default character set. See Section 10.14,
           “Character Set Configuration”. If no character set is specified,
           mysqldump uses utf8.

       ·   --defaults-extra-file=file_name

           Read this option file after the global option file but (on Unix)
           before the user option file. If the file does not exist or is
           otherwise inaccessible, an error occurs. Before MySQL 5.5.8,
           file_name must be the full path name to the file. As of MySQL
           5.5.8, the name is interpreted relative to the current directory if
           given as a relative path name.

       ·   --defaults-file=file_name

           Use only the given option file. If the file does not exist or is
           otherwise inaccessible, an error occurs. Before MySQL 5.5.8,
           file_name must be the full path name to the file. As of MySQL
           5.5.8, the name is interpreted relative to the current directory if
           given as a relative path name.

       ·   --defaults-group-suffix=str

           Read not only the usual option groups, but also groups with the
           usual names and a suffix of str. For example, mysqldump normally
           reads the [client] and [mysqldump] groups. If the
           --defaults-group-suffix=_other option is given, mysqldump also
           reads the [client_other] and [mysqldump_other] groups.

       ·   --delayed-insert

           Write INSERT DELAYED statements rather than INSERT statements.

       ·   --delete-master-logs

           On 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.

       ·   --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 faster
           because the indexes are created after all rows are inserted. This
           option is effective only for nonunique indexes of MyISAM tables. It
           has no effect for other tables.

       ·   --dump-date

           If the --comments option is 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]

           This option is similar to --master-data except that it is used to
           dump a replication slave server to produce a dump file that can be
           used to set up another server as a slave that has the same master
           as the dumped server. 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 slave's master. These are the
           master server coordinates from which the slave should start
           replicating.

           --dump-slave causes the coordinates from the master to be used
           rather than those of the dumped server, as is done by the
           --master-data option. In addition, specfiying this option causes
           the --master-data option to be overridden, if used, and effectively
           ignored.

           The option value is handled the same way as for --master-data
           (setting no value or 1 causes a CHANGE MASTER TO statement to be
           written to the dump, setting 2 causes the statement to be written
           but encased in SQL comments) and has the same effect as
           --master-data in terms of enabling or disabling other options and
           in how locking is handled.

           This option causes mysqldump to stop the slave SQL thread before
           the dump and restart it again after.

           In conjunction with --dump-slave, the --apply-slave-statements and
           --include-master-host-port options can also be used.

           This option was added in MySQL 5.5.3.

       ·   --events, -E

           Include Event Scheduler events for the dumped databases in the
           output. This option requires the EVENT privileges for those
           databases.

       ·   --extended-insert, -e

           Write INSERT statements using multiple-row syntax that includes
           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=...

           These options are used with the --tab option and have the same
           meaning as the corresponding FIELDS clauses for LOAD DATA INFILE.
           See Section 13.2.6, “LOAD DATA INFILE Syntax”.

       ·   --first-slave

           Deprecated. Use --lock-all-tables instead.  --first-slave was
           removed in MySQL 5.5.3.

       ·   --flush-logs, -F

           Flush the MySQL server log files before starting the dump. This
           option requires the RELOAD privilege. If you use this option in
           combination with the --all-databases option, the logs are flushed
           for each database dumped. The exception is when using
           --lock-all-tables, --master-data, or (as of MySQL 5.5.21)
           --single-transaction: In this case, the logs are flushed only once,
           corresponding to the moment that all tables are locked by FLUSH
           TABLES WITH READ LOCK. If you want your dump and the log flush to
           happen at exactly the same moment, you should use --flush-logs
           together with --lock-all-tables, --master-data, or
           --single-transaction.

       ·   --flush-privileges

           Add a FLUSH PRIVILEGES statement to the dump output 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.

       ·   --force, -f

           Continue 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, 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.

       ·   --enable-cleartext-plugin

           Enable the mysql_clear_password cleartext authentication plugin.
           (See Section 6.5.1.3, “Client-Side Cleartext Pluggable
           Authentication”.)

           This option was added in MySQL 5.5.47.

       ·   --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 columns using hexadecimal notation (for example, 'abc'
           becomes 0x616263). The affected data types are BINARY, VARBINARY,
           the BLOB types, and BIT.

       ·   --include-master-host-port

           For the CHANGE MASTER TO statement in a slave dump produced with
           the --dump-slave option, add MASTER_HOST and MASTER_PORT options
           for the host name and TCP/IP port number of the slave's master.
           This option was added in MySQL 5.5.3.

       ·   --ignore-table=db_name.tbl_name

           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.

       ·   --insert-ignore

           Write INSERT IGNORE statements rather than INSERT statements.

       ·   --lines-terminated-by=...

           This option is used with the --tab option and has the same meaning
           as the corresponding LINES clause for LOAD DATA INFILE. See
           Section 13.2.6, “LOAD DATA INFILE Syntax”.

       ·   --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.

       ·   --lock-tables, -l

           For each dumped database, lock all tables to be dumped before
           dumping them. The tables are locked with READ LOCAL to permit
           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.

           Some options, such as --opt, automatically enable --lock-tables. If
           you want to override this, use --skip-lock-tables at the end of the
           option list.

       ·   --log-error=file_name

           Log warnings and errors by appending them to the named file. The
           default is to do no logging.

       ·   --master-data[=value]

           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 after you
           load the dump file into the slave.

           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 is not written as a comment and takes effect when the
           dump file is reloaded. If no option value is specified, the default
           value is 1.

           This option requires the RELOAD privilege and the binary log must
           be enabled.

           The --master-data option automatically turns off --lock-tables. It
           also turns on --lock-all-tables, unless --single-transaction 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 --single-transaction). 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. In MySQL 5.5.3 and higher, you can create such a
           dump using the --dump-slave option, which overrides --master-data
           and causes it to be ignored if both options are used.

           Before MySQL 5.5.3, use the following procedure on the existing
           slave:

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

                   mysql> STOP SLAVE SQL_THREAD;
                   mysql> SHOW SLAVE 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.

            3. Dump the slave server:

                   shell> mysqldump --master-data=2 --all-databases > dumpfile

               Using --master-data=2 works only if binary logging has been
               enabled on the slave. Otherwise, mysqldump fails with the error
               Binlogging on server not active. In this case you must handle
               any locking issues in another manner, using one or more of
               --add-locks, --lock-tables, --lock-all-tables, or
               --single-transaction, as required by your application and
               environment.

            4. Restart the slave:

                   mysql> START SLAVE;

            5. On the new slave, load the dump file:

                   shell> mysql < dumpfile

            6. 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.

       ·   --no-autocommit

           Enclose the INSERT statements for each dumped table within SET
           autocommit = 0 and COMMIT statements.

       ·   --no-create-db, -n

           Suppress the CREATE DATABASE statements that are otherwise included
           in the output if the --databases or --all-databases option is
           given.

       ·   --no-create-info, -t

           Do not write CREATE TABLE statements that create each dumped table.

               Note
               This option does not exclude statements creating log file
               groups or tablespaces from mysqldump output; however, you can
               use the --no-tablespaces option for this purpose.

       ·   --no-data, -d

           Do 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-defaults

           Do not read any option files. If program startup fails due to
           reading unknown options from an option file, --no-defaults can be
           used to prevent them from being read.

       ·   --no-set-names, -N

           This has the same effect as --skip-set-charset.

       ·   --no-tablespaces, -y

           This option suppresses all CREATE LOGFILE GROUP and CREATE
           TABLESPACE statements in the output of mysqldump.

       ·   --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.

           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-primary

           Dump each table's rows sorted 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 operation take considerably longer.

       ·   --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, mysqldump prompts for
           one.

           Specifying a password on the command line should be considered
           insecure. See Section 6.1.2.1, “End-User Guidelines for Password
           Security”. You can use an option file to avoid giving the password
           on the command line.

       ·   --pipe, -W

           On Windows, connect to the server using a named pipe. This option
           applies only if the server supports named-pipe connections.

       ·   --plugin-dir=dir_name

           The directory in which to look for plugins. Specify this option if
           the --default-auth option is used to specify an authentication
           plugin but mysqldump does not find it. See Section 6.3.6,
           “Pluggable Authentication”.

           This option was added in MySQL 5.5.9.

       ·   --port=port_num, -P port_num

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

       ·   --print-defaults

           Print the program name and all options that it gets from option
           files.

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

           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
           permissible values, see Section 4.2.2, “Connecting to the MySQL
           Server”.

       ·   --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 identifiers (such as database, table, and column names)
           within ` 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.

       ·   --replace

           Write REPLACE statements rather than INSERT statements.

       ·   --result-file=file_name, -r file_name

           Direct output to the named file. The result file is created and its
           previous contents overwritten, even if an error occurs while
           generating the dump.

           This option should be used on Windows to prevent newline \n
           characters from being converted to \r\n carriage return/newline
           sequences.

       ·   --routines, -R

           Include stored routines (procedures and functions) for the dumped
           databases in the output. This option requires the SELECT privilege
           for the mysql.proc table.

           The output generated by using --routines contains CREATE PROCEDURE
           and CREATE FUNCTION statements to create the routines. However,
           these statements do not include attributes such as the routine
           creation and modification timestamps, so when the routines are
           reloaded, they are created with timestamps equal to the reload
           time.

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

           Prior to MySQL 5.5.21, this option had no effect when used together
           with the --xml option. (Bug #11760384, Bug #52792)

       ·   --set-charset

           Write SET NAMES default_character_set to the output. This option is
           enabled by default. To suppress the SET NAMES statement, use
           --skip-set-charset.

       ·   --shared-memory-base-name=name

           On Windows, the shared-memory name to use, for connections made
           using shared memory to a local server. The default value is MYSQL.
           The shared-memory name is case-sensitive.

           The server must be started with the --shared-memory option to
           enable shared-memory connections.

       ·   --single-transaction

           This option sets the transaction isolation mode to REPEATABLE READ
           and 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 START TRANSACTION 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
           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, 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 that is 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.

           This option is not supported for NDB 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.

           To dump large tables, combine the --single-transaction option with
           the --quick option.

       ·   --skip-comments

           See the description for the --comments option.

       ·   --skip-opt

           See the description for the --opt option.

       ·   --socket=path, -S path

           For connections to localhost, the Unix socket file to use, or, on
           Windows, the name of the named pipe to use.

       ·   --ssl*

           Options that begin with --ssl specify whether to connect to the
           server using SSL and indicate where to find SSL keys and
           certificates. See Section 6.4.2, “Command Options for Encrypted
           Connections”.

       ·   --tab=dir_name, -T dir_name

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

               Note
               This option should be used only when mysqldump is run on the
               same machine as the mysqld server. Because the server creates
               *.txt files in the directory that you specify, the directory
               must be writable by the server and the MySQL account that you
               use must have the FILE privilege. Because mysqldump creates
               *.sql in the same directory, it must be writable by your system
               login account.
           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.

       ·   --tables

           Override the --databases or -B option.  mysqldump regards all name
           arguments following the option as table names.

       ·   --triggers

           Include triggers for each dumped table in the output. This option
           is enabled by default; disable it with --skip-triggers.

           To be able to dump a table's triggers, you must have the TRIGGER
           privilege for the table.

       ·   --tz-utc

           This 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.

       ·   --user=user_name, -u user_name

           The MySQL user name to use when connecting to the server.

       ·   --verbose, -v

           Verbose mode. Print more information about what the program does.

       ·   --version, -V

           Display version information and exit.

       ·   --where='where_condition', -w 'where_condition'

           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.

           Examples:

               --where="user='jimf'"
               -w"userid>1"
               -w"userid<1"

       ·   --xml, -X

           Write dump output as well-formed XML.

           NULL, 'NULL', and Empty Values: 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.

           ┌──────────────────────┬─────────────────────────────────┐
           │Value:                │ XML 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. (See the section called “MYSQL
           OPTIONS”.)

           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="http://www.w3.org/2001/XMLSchema-instance">
               <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_structure>
               <table_data name="City">
               <row>
               <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>
               </row>
               ...
               <row>
               <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>
               </row>
               </table_data>
               </database>
               </mysqldump>

           Prior to MySQL 5.5.21, this option prevented the --routines option
           from working correctly—that is, no stored routines, triggers, or
           events could be dumped in XML format. (Bug #11760384, Bug #52792)

       You can also set the following variables by using --var_name=value
       syntax:

       ·   max_allowed_packet

           The maximum size of the buffer for client/server communication. The
           default is 24MB, the maximum is 1GB.

       ·   net_buffer_length

           The 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 bytes long. If you increase this variable, ensure
           that the MySQL server net_buffer_length system variable has a value
           at least this large.

       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 MySQL 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 --master-data --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 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.

       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 5.4.4, “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

       Or:

           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.

       For more information on making backups, see Section 7.2, “Database
       Backup Methods”, and Section 7.3, “Example Backup and Recovery
       Strategy”.

       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 C.5, “Restrictions on Views”.

COPYRIGHT
       Copyright © 1997, 2018, Oracle and/or its affiliates. All rights
       reserved.

       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.

       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.

       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/.


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/.

AUTHOR
       Oracle Corporation (http://dev.mysql.com/).



MySQL 5.5                         02/25/2018                      MYSQLDUMP(1)

mysqldump  Ver 10.13 Distrib 5.5.60, for debian-linux-gnu (x86_64)
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Dumping structure and contents of MySQL databases and tables.
Usage: mysqldump [OPTIONS] database [tables]
OR     mysqldump [OPTIONS] --databases [OPTIONS] DB1 [DB2 DB3...]
OR     mysqldump [OPTIONS] --all-databases [OPTIONS]

Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf /usr/etc/my.cnf ~/.my.cnf 
The following groups are read: mysqldump client
The following options may be given as the first argument:
--print-defaults        Print the program argument list and exit.
--no-defaults           Don'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.
  -A, --all-databases Dump all the databases. This will be same as --databases
                      with all databases selected.
  -Y, --all-tablespaces 
                      Dump all the tablespaces.
  -y, --no-tablespaces 
                      Do not dump any tablespace information.
  --add-drop-database Add a DROP DATABASE before each create.
  --add-drop-table    Add a DROP TABLE before each create.
                      (Defaults to on; use --skip-add-drop-table to disable.)
  --add-locks         Add locks around INSERT statements.
                      (Defaults to on; use --skip-add-locks to disable.)
  --allow-keywords    Allow creation of column names that are keywords.
  --apply-slave-statements 
                      Adds 'STOP SLAVE' prior to 'CHANGE MASTER' and 'START
                      SLAVE' to bottom of dump.
  --character-sets-dir=name 
                      Directory for character set files.
  -i, --comments      Write additional information.
                      (Defaults to on; use --skip-comments to disable.)
  --compatible=name   Change the dump to be compatible with a given mode. By
                      default tables are dumped in a format optimized for
                      MySQL. Legal modes are: ansi, mysql323, mysql40,
                      postgresql, oracle, mssql, db2, maxdb, no_key_options,
                      no_table_options, no_field_options. One can use several
                      modes separated by commas. Note: Requires MySQL server
                      version 4.1.0 or higher. This option is ignored with
                      earlier server versions.
  --compact           Give less verbose output (useful for debugging). Disables
                      structure comments and header/footer constructs.  Enables
                      options --skip-add-drop-table --skip-add-locks
                      --skip-comments --skip-disable-keys --skip-set-charset.
  -c, --complete-insert 
                      Use complete insert statements.
  -C, --compress      Use compression in server/client protocol.
  -a, --create-options 
                      Include all MySQL specific create options.
                      (Defaults to on; use --skip-create-options to disable.)
  -B, --databases     Dump several databases. Note the difference in usage; in
                      this case no tables are given. All name arguments are
                      regarded as database names. 'USE db_name;' will be
                      included in the output.
  -#, --debug[=#]     This is a non-debug version. Catch this and exit.
  --debug-check       Check memory and open file usage at exit.
  --debug-info        Print some debug info at exit.
  --default-character-set=name 
                      Set the default character set.
  --delayed-insert    Insert rows with INSERT DELAYED.
  --delete-master-logs 
                      Delete logs on master after backup. This 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.
                      (Defaults to on; use --skip-disable-keys to disable.)
  --dump-slave[=#]    This causes the binary log position and filename of the
                      master to be appended to the dumped data output. Setting
                      the value to 1, will printit as a CHANGE MASTER command
                      in the dumped data output; if equal 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.
  -E, --events        Dump events.
  -e, --extended-insert 
                      Use multiple-row INSERT syntax that include several
                      VALUES lists.
                      (Defaults to on; use --skip-extended-insert to disable.)
  --fields-terminated-by=name 
                      Fields in the output file are terminated by the given
                      string.
  --fields-enclosed-by=name 
                      Fields in the output file are enclosed by the given
                      character.
  --fields-optionally-enclosed-by=name 
                      Fields in the output file are optionally enclosed by the
                      given character.
  --fields-escaped-by=name 
                      Fields in the output file are escaped by the given
                      character.
  -F, --flush-logs    Flush logs file in server before starting dump. Note that
                      if you dump many databases at once (using the option
                      --databases= or --all-databases), the logs will be
                      flushed for each database dumped. The exception is when
                      using --lock-all-tables or --master-data: in this case
                      the logs will be flushed only once, corresponding to the
                      moment all tables are locked. So if you want your dump
                      and the log flush to happen at the same exact moment you
                      should use --lock-all-tables or --master-data with
                      --flush-logs.
  --flush-privileges  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
                      restore. 
  -f, --force         Continue even if we get an SQL error.
  -?, --help          Display this help message and exit.
  --hex-blob          Dump binary strings (BINARY, VARBINARY, BLOB) in
                      hexadecimal format.
  -h, --host=name     Connect to host.
  --ignore-table=name Do 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.
  --include-master-host-port 
                      Adds 'MASTER_HOST=<host>, MASTER_PORT=<port>' to 'CHANGE
                      MASTER TO..' in dump produced with --dump-slave.
  --insert-ignore     Insert rows with INSERT IGNORE.
  --lines-terminated-by=name 
                      Lines in the output file are terminated by the given
                      string.
  -x, --lock-all-tables 
                      Locks all tables across all databases. This is achieved
                      by taking a global read lock for the duration of the
                      whole dump. Automatically turns --single-transaction and
                      --lock-tables off.
  -l, --lock-tables   Lock all tables for read.
                      (Defaults to on; use --skip-lock-tables to disable.)
  --log-error=name    Append warnings and errors to given file.
  --master-data[=#]   This causes the binary log position and filename to be
                      appended to the output. If equal to 1, will print it as a
                      CHANGE MASTER command; if equal 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.
  --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-autocommit     Wrap tables with autocommit/commit statements.
  -n, --no-create-db  Suppress the CREATE DATABASE ... IF EXISTS statement that
                      normally is output for each dumped database if
                      --all-databases or --databases is given.
  -t, --no-create-info 
                      Don't write table creation info.
  -d, --no-data       No row information.
  -N, --no-set-names  Same as --skip-set-charset.
  --opt               Same as --add-drop-table, --add-locks, --create-options,
                      --quick, --extended-insert, --lock-tables, --set-charset,
                      and --disable-keys. Enabled by default, disable with
                      --skip-opt.
  --order-by-primary  Sorts each table's rows by primary key, or first unique
                      key, if such a key exists.  Useful when dumping a MyISAM
                      table to be loaded into an InnoDB table, but will make
                      the dump itself take considerably longer.
  -p, --password[=name] 
                      Password to use when connecting to server. If password is
                      not given it's solicited on the tty.
  -P, --port=#        Port number to use for connection.
  --protocol=name     The protocol to use for connection (tcp, socket, pipe,
                      memory).
  -q, --quick         Don't buffer query, dump directly to stdout.
                      (Defaults to on; use --skip-quick to disable.)
  -Q, --quote-names   Quote table and column names with backticks (`).
                      (Defaults to on; use --skip-quote-names to disable.)
  --replace           Use REPLACE INTO instead of INSERT INTO.
  -r, --result-file=name 
                      Direct output to a given file. This option should be used
                      in systems (e.g., DOS, Windows) that use carriage-return
                      linefeed pairs (\r\n) to separate text lines. This option
                      ensures that only a single newline is used.
  -R, --routines      Dump stored routines (functions and procedures).
  --set-charset       Add 'SET NAMES default_character_set' to the output.
                      (Defaults to on; use --skip-set-charset to disable.)
  --single-transaction 
                      Creates a consistent snapshot by dumping all tables in a
                      single transaction. Works ONLY for tables stored in
                      storage engines which support multiversioning (currently
                      only InnoDB does); the dump is NOT guaranteed to be
                      consistent for other storage engines. While a
                      --single-transaction 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, as consistent snapshot is not isolated
                      from them. Option automatically turns off --lock-tables.
  --dump-date         Put a dump date to the end of the output.
                      (Defaults to on; use --skip-dump-date to disable.)
  --skip-opt          Disable --opt. Disables --add-drop-table, --add-locks,
                      --create-options, --quick, --extended-insert,
                      --lock-tables, --set-charset, and --disable-keys.
  -S, --socket=name   The socket file to use for connection.
  --ssl               Enable SSL for connection (automatically enabled with
                      other flags).
  --ssl-ca=name       CA file in PEM format (check OpenSSL docs, implies
                      --ssl).
  --ssl-capath=name   CA directory (check OpenSSL docs, implies --ssl).
  --ssl-cert=name     X509 cert in PEM format (implies --ssl).
  --ssl-cipher=name   SSL cipher to use (implies --ssl).
  --ssl-key=name      X509 key in PEM format (implies --ssl).
  --ssl-verify-server-cert 
                      Verify server's "Common Name" in its cert against
                      hostname used when connecting. This option is disabled by
                      default.
  --ssl-mode=name     SSL connection mode.
  -T, --tab=name      Create tab-separated textfile for each table to given
                      path. (Create .sql and .txt files.) NOTE: This only works
                      if mysqldump is run on the same machine as the mysqld
                      server.
  --tables            Overrides option --databases (-B).
  --triggers          Dump triggers for each dumped table.
                      (Defaults to on; use --skip-triggers to disable.)
  --tz-utc            SET TIME_ZONE='+00:00' at top of dump to allow dumping of
                      TIMESTAMP data when a server has data in different time
                      zones or data is being moved between servers with
                      different time zones.
                      (Defaults to on; use --skip-tz-utc to disable.)
  -u, --user=name     User for login if not current user.
  -v, --verbose       Print info about the various stages.
  -V, --version       Output version information and exit.
  -w, --where=name    Dump only selected records. Quotes are mandatory.
  -X, --xml           Dump a database as well formed XML.
  --plugin-dir=name   Directory for client-side plugins.
  --default-auth=name Default authentication client-side plugin to use.
  --enable-cleartext-plugin 
                      Enable/disable the clear text authentication plugin.