When you execute GRANT SELECT ON store.catalog TO 'wordpress'@'%';
, mysqld wants to insert a row into the grant table mysql.tables_priv
. Here is mysql.tables_priv:
mysql> show create table mysql.tables_priv\G
*************************** 1. row ***************************
Table: tables_priv
Create Table: CREATE TABLE `tables_priv` (
`Host` char(60) COLLATE utf8_bin NOT NULL DEFAULT '',
`Db` char(64) COLLATE utf8_bin NOT NULL DEFAULT '',
`User` char(16) COLLATE utf8_bin NOT NULL DEFAULT '',
`Table_name` char(64) COLLATE utf8_bin NOT NULL DEFAULT '',
`Grantor` char(77) COLLATE utf8_bin NOT NULL DEFAULT '',
`Timestamp` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
`Table_priv` set('Select','Insert','Update','Delete','Create','Drop','Grant','References','Index','Alter','Create View','Show view','Trigger') CHARACTER SET utf8 NOT NULL DEFAULT '',
`Column_priv` set('Select','Insert','Update','References') CHARACTER SET utf8 NOT NULL DEFAULT '',
PRIMARY KEY (`Host`,`Db`,`User`,`Table_name`),
KEY `Grantor` (`Grantor`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT='Table privileges'
1 row in set (0.00 sec)
mysql>
Since you want to insert a row into mysql.table_priv
where user='wordpress' and host='%', there has to exist a row in mysql.user
where user='wordpress' and host='%'.
You also mentioned that you are using MySQL Workbench. You must be using 'root'@'localhost'
. That would usually have all rights and a password.
If you want to just allow anonymous SELECT against that table, first run this:
GRANT USAGE ON *.* TO 'wordpress'@'%';
This will place wordpress@'%'
into mysql.user
. Afterwards, GRANT SELECT ON store.catalog TO 'wordpress'@'%'
should run just fine.
You will have to see what other wordpress entries are in mysql.user
. This should show what SQL GRANT commands you need:
SELECT CONCAT('GRANT SELECT ON store.catalog TO ',userhost,';') GrantCommand
FROM
(
SELECT CONCAT('''',user,'''@''',host,'''') userhost
FROM mysql.user WHERE user='wordpress'
) A;
You could copy just the the "mysql" database away to another location and start another daemon on it. Get the SHA1 or DES hash stored in the user table for a user with SUPER privs (usually root, but sometimes renamed for security through obscurity).
Then connect to the mysql using a modified version of the client library that makes mysql_real_connect() support using a pre-hashed password instead of having it take the password plaintext. This should be trivial.
You won't ever know the actual password, but with the hash and a modified client you'll be able to log in anyway.
You can then make any modifications to permissions, create necessary schema and tables and flush privileges.
I'll leave the security implications of such practices up to you.
Best Answer
From the docs,
mysql.db
is the table that handles database-specific GRANTS. That is to say, if you explicitly indicated a database in yourGRANT
command, it would show up in this table:So the user
bar@localhost
would have SELECT and INSERT marked as 'Y' in themysql.db
table.To remove entries from this table, likewise you need to specify the database:
Issuing a
REVOKE INSERT ON *.*
statement (all databases) will not affect this table.Also, a
DROP USER
statement will clean up all the entries in the variousmysql.*
tables that deal with user authentication, such asmysql.db
.