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This section describes how to use mysqldump to create SQL-format dump files. For information about reloading such dump files, see Section 7.4.2, "Reloading SQL-Format Backups".
By default, mysqldump writes information as SQL statements to the standard output. You can save the output in a file:
shell> mysqldump [arguments
]
> file_name
To dump all databases, invoke mysqldump with the --all-databases
option:
shell> mysqldump --all-databases > dump.sql
To dump only specific databases, name them on the command line and use the --databases
option:
shell> mysqldump --databases db1 db2 db3 >
dump.sql
The --databases
option causes all names on the command line to be treated as database names. Without this option, mysqldump treats the first name as a database name and those
following as table names.
With --all-databases
or --databases
, mysqldump writes CREATE DATABASE
and USE
statements prior to the dump output for each database. This ensures that when
the dump file is reloaded, it creates each database if it does not exist and makes it the default database so
database contents are loaded into the same database from which they came. If you want to cause the dump file to
force a drop of each database before recreating it, use the --add-drop-database
option as well. In this case, mysqldump writes a DROP DATABASE
statement preceding each CREATE DATABASE
statement.
To dump a single database, name it on the command line:
shell> mysqldump --databases test >
dump.sql
In the single-database case, it is permissible to omit the --databases
option:
shell> mysqldump test >
dump.sql
The difference between the two preceding commands is that without --databases
, the dump output contains no CREATE DATABASE
or USE
statements. This has several implications:
When you reload the dump file, you must specify a default database name so that the server knows which database to reload.
For reloading, you can specify a database name different from the original name, which enables you to reload the data into a different database.
If the database to be reloaded does not exist, you must create it first.
Because the output will contain no CREATE DATABASE
statement, the --add-drop-database
option has no effect. If you use it, it produces no DROP DATABASE
statement.
To dump only specific tables from a database, name them on the command line following the database name:
shell> mysqldump test t1 t3 t7 >
dump.sql