CREATE ROLE IF NOT EXISTS role1 WITH ADMIN user1; Warnings: Note 1449 The user specified as a definer ('user1'@'%') does not exist SELECT * FROM mysql.roles_mapping; Host User Role Admin_option % user1 role1 Y DROP ROLE role1; CREATE OR REPLACE ROLE role1 WITH ADMIN user2; Warnings: Note 1449 The user specified as a definer ('user2'@'%') does not exist SELECT * FROM mysql.roles_mapping WHERE Role='role1'; Host User Role Admin_option % user2 role1 Y CREATE OR REPLACE ROLE role1 WITH ADMIN user3; Warnings: Note 1449 The user specified as a definer ('user3'@'%') does not exist SELECT * FROM mysql.roles_mapping WHERE Role='role1'; Host User Role Admin_option % user3 role1 Y CREATE ROLE IF NOT EXISTS role1 WITH ADMIN user4; Warnings: Note 1449 The user specified as a definer ('user4'@'%') does not exist Note 1975 Can't create role 'role1'; it already exists SELECT * FROM mysql.roles_mapping WHERE Role='role1'; Host User Role Admin_option % user3 role1 Y DROP ROLE IF EXISTS role1; SELECT * FROM mysql.roles_mapping WHERE Role='role1'; Host User Role Admin_option DROP ROLE IF EXISTS role1; Warnings: Note 1976 Can't drop role 'role1'; it doesn't exist CREATE ROLE role_1; CREATE ROLE IF NOT EXISTS role_1; Warnings: Note 1975 Can't create role 'role_1'; it already exists CREATE OR REPLACE ROLE role_1; CREATE OR REPLACE ROLE IF NOT EXISTS role_1; ERROR HY000: Incorrect usage of OR REPLACE and IF NOT EXISTS CREATE ROLE role_1; ERROR HY000: Operation CREATE ROLE failed for 'role_1' CREATE USER u1@localhost; REVOKE SHOW DATABASES ON *.* FROM 'u1'@'localhost'; GRANT SHOW DATABASES ON *.* TO role_1; GRANT role_1 TO u1@localhost; SELECT CURRENT_USER; CURRENT_USER u1@localhost SHOW DATABASES; Database information_schema test SELECT CURRENT_ROLE; CURRENT_ROLE NULL SET ROLE role_1; SELECT CURRENT_ROLE; CURRENT_ROLE role_1 SHOW DATABASES; Database information_schema mtr mysql performance_schema test SET ROLE NONE; # Clearing up DROP ROLE role_1; DROP ROLE IF EXISTS role_1; Warnings: Note 1976 Can't drop role 'role_1'; it doesn't exist DROP ROLE role_1; ERROR HY000: Operation DROP ROLE failed for 'role_1' DROP USER u1@localhost; CREATE ROLE r; GRANT SHOW DATABASES ON *.* TO r; CREATE USER foo; CREATE USER bar; GRANT r TO foo; CREATE OR REPLACE USER foo IDENTIFIED WITH non_existing_plugin; ERROR HY000: Plugin 'non_existing_plugin' is not loaded DROP ROLE r; DROP USER bar;