-- Grab the users with global permissions, 
-- with permissions to the databases you want, 
-- and tables/stored procedures in it.
mysql> SELECT u.* INTO OUTFILE '/tmp/user.txt'
	FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' ESCAPED BY '\\'
	LINES TERMINATED BY '\n'
	FROM
		mysql.USER u
	WHERE
		u.Select_priv='Y'
	UNION
	SELECT u.*
	FROM
		mysql.USER u,
		mysql.db d
	WHERE
		d.Db IN('db1', 'db2', ...) AND
		d.USER = u.USER
	UNION
	SELECT u.*
	FROM
		mysql.USER u,
		mysql.tables_priv t
	WHERE
		t.Db IN('db1', 'db2', ...) AND
		t.USER = u.USER
	UNION
	SELECT u.*
	FROM
		mysql.USER u,
		mysql.procs_priv p
	WHERE
		p.Db IN('db1', 'db2', ...) AND
		p.USER = u.USER;
 
-- Now, grab the database permissions, and those of objects in the database.
mysql> SELECT * INTO OUTFILE '/tmp/db.txt'
	FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' ESCAPED BY '\\'
	LINES TERMINATED BY '\n'
	FROM
		mysql.db
	WHERE
		Db IN('db1', 'db2', ...);
mysql> SELECT * INTO OUTFILE '/tmp/tables_priv.txt'
	FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' ESCAPED BY '\\'
	LINES TERMINATED BY '\n'
	FROM
		mysql.tables_priv
	WHERE
		Db IN('db1', 'db2', ...);
mysql> SELECT * INTO OUTFILE '/tmp/procs_priv.txt'
	FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' ESCAPED BY '\\'
	LINES TERMINATED BY '\n'
	FROM
		mysql.procs_priv
	WHERE
		Db IN('db1', 'db2', ...);

mysql> LOAD DATA INFILE '/tmp/user.txt'
	FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' ESCAPED BY '\\'
	LINES TERMINATED BY '\n'
	INTO TABLE mysql.USER;
mysql> LOAD DATA INFILE '/tmp/db.txt'
	FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' ESCAPED BY '\\'
	LINES TERMINATED BY '\n'
	INTO TABLE mysql.db;
mysql> LOAD DATA INFILE '/tmp/tables_priv.txt'
	FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' ESCAPED BY '\\'
	LINES TERMINATED BY '\n'
	INTO TABLE mysql.tables_priv;
mysql> LOAD DATA INFILE '/tmp/procs_priv.txt'
	FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' ESCAPED BY '\\'
	LINES TERMINATED BY '\n'
	INTO TABLE mysql.procs_priv;