Populating mysql database with grants from mysql dump

Question

I've taken a mysql dump of a database using the command:

mysqldump --single-transaction --all-databases --flush-privileges -h HOST -u USER -p PASSWORD

I purposefully used the --all-databases flag to make sure that I got all the users I had created and the permissions they had granted. But when I run the import to a new database as the root user, I get this error: Access denied for user 'root'@'%' to database 'mysql'

Is there a different way to copy over users and permissions from one database to another?

Answer 1

I use a SHOW GRANTS statement to get the privileges, for example:

SHOW GRANTS FOR foo@'%'

Which returns something like this:

Grants for foo@%                                                                                                                  
--------------------------------------------------------------------------------------------------
GRANT USAGE ON *.* TO 'foo'@'%' IDENTIFIED BY PASSWORD '*B3CD------------------------------------'
GRANT SELECT, INSERT, UPDATE, DELETE, CREATE TEMPORARY TABLES, EXECUTE ON `db`.* TO 'foo'@'%'
GRANT SELECT ON `mysql`.`proc` TO 'foo'@'%'

I can easily take the output, add the semicolon statement terminators, make any other necessary modifications, and execute them on another database.

And just repeat that for whichever users I need to migrate.