Find users having grants on a table in MySQL

Question

We grant access to users with the following

grant select, insert, update, delete on product_events to 'product_admin'@'%' ;

Now, like this there are a lot of tables, and a lot of users.

I want to find all users having any grants on a particular table

That is, given product_events table, I would like to get 'product_admin'@'%'

Answer 1

This messy query should give you every user that can access product_db.product_events

SELECT user,host,'Global' Level FROM mysql.user WHERE
select_priv='Y' OR insert_priv='Y' OR update_priv='Y' OR delete_priv='Y'
UNION
SELECT user,host,'DB' FROM mysql.db
WHERE db='product_db' AND
(select_priv='Y' OR insert_priv='Y' OR update_priv='Y' OR delete_priv='Y')
UNION
SELECT user,host,'Table' FROM mysql.tables_priv
WHERE db='product_db' AND table_name='product_events';

If you are looking for users with all four(4) permissions (SELECT,INSERT,UPDATE and DELETE grants), then use this (basically using AND instead of OR)

SELECT user,host,'Global' Level FROM mysql.user WHERE
select_priv='Y' AND insert_priv='Y' AND update_priv='Y' AND delete_priv='Y'
UNION
SELECT user,host,'DB' FROM mysql.db
WHERE db='product_db' AND
(select_priv='Y' AND insert_priv='Y' AND update_priv='Y' AND delete_priv='Y')
UNION
SELECT user,host,'Table' FROM mysql.tables_priv
WHERE db='product_db' AND table_name='product_events';

NOTE : Table level privileges are even more messier to check since the grants are listed as a set rather than as individual columns

mysql> desc mysql.tables_priv;
+-------------+-----------------------------------------------------------------------------------------------------------------------------------+------+-----+-------------------+-----------------------------+
| Field       | Type                                                                                                                              | Null | Key | Default           | Extra                       |
+-------------+-----------------------------------------------------------------------------------------------------------------------------------+------+-----+-------------------+-----------------------------+
| Host        | char(60)                                                                                                                          | NO   | PRI |                   |                             |
| Db          | char(64)                                                                                                                          | NO   | PRI |                   |                             |
| User        | char(16)                                                                                                                          | NO   | PRI |                   |                             |
| Table_name  | char(64)                                                                                                                          | NO   | PRI |                   |                             |
| Grantor     | char(77)                                                                                                                          | NO   | MUL |                   |                             |
| Timestamp   | timestamp                                                                                                                         | NO   |     | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP |
| Table_priv  | set('Select','Insert','Update','Delete','Create','Drop','Grant','References','Index','Alter','Create View','Show view','Trigger') | NO   |     |                   |                             |
| Column_priv | set('Select','Insert','Update','References')                                                                                      | NO   |     |                   |                             |
+-------------+-----------------------------------------------------------------------------------------------------------------------------------+------+-----+-------------------+-----------------------------+
8 rows in set (0.00 sec)

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