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Summary: in this tutorial, you will learn how to use the MySQL GRANT statement to grant privileges to user accounts.

Introduction to the MySQL GRANT statement

The CREATE USER statement creates one or more user accounts with no privileges. It means that the user accounts can log in to the MySQL Server, but cannot do anything such as selecting a database and querying data from tables.

To allow user accounts to work with database objects, you need to grant the user accounts privileges. And the GRANT statement grants a user account one or more privileges.

The following illustrates the basic syntax of the GRANT statement:

GRANT privilege [,privilege],.. 
ON privilege_level 
TO account_name;
Code language: SQL (Structured Query Language) (sql)

In this syntax:

First, specify one or more privileges after the GRANT keyword. If you grant multiple privileges, you need to separate privileges by commas.

This example grants the SELECT privilege on the table employees  in the sample database to the user acount bob@localhost:

GRANT SELECT
ON employees
TO bob@localhost;
Code language: SQL (Structured Query Language) (sql)

The following example grants UPDATE, DELETE, and INSERT privileges on the table employees to bob@localhost:

GRANT INSERT, UPDATE, DELETE
ON employees 
TO bob@localhost;
Code language: SQL (Structured Query Language) (sql)

Second, specify the privilege_level that determines the level to which the privileges apply.

MySQL supports the following main privilege levels:

Global privileges apply to all databases in a MySQL Server. To assign global privileges, you use the *.* syntax, for example:

GRANT SELECT 
ON *.* 
TO bob@localhost;
Code language: SQL (Structured Query Language) (sql)

The account user bob@localhost can query data from all tables in all database of the current MySQL Server.

Database privileges apply to all objects in a database. To assign database-level privileges, you use the ON database_name.* syntax, for example:

GRANT INSERT 
ON classicmodels.* 
TO bob@localhost;
Code language: SQL (Structured Query Language) (sql)

In this example, bob@localhost can insert data into all tables in the classicmodels database.

Table privileges apply to all columns in a table. To assign table-level privileges, you use the ON database_name.table_name syntax, for example:

GRANT DELETE 
ON classicmodels.employees 
TO bob@localhsot;
Code language: SQL (Structured Query Language) (sql)

In this example, bob@localhost can delete rows from the table employees in the database classicmodels.

If you skip the database name, MySQL uses the default database or issues an error if there is no default database.

Column privileges apply to single columns in a table.  You must specify the column or columns for each privilege, for example:

GRANT 
   SELECT (employeeNumner,lastName, firstName,email), 
   UPDATE(lastName) 
ON employees 
TO bob@localhost;
Code language: SQL (Structured Query Language) (sql)

In this example, bob@localhost can select data from four columns employeeNumber, lastName, firstName, and email and update only the lastName column in the employees table.

Stored routine privileges apply to stored procedures and stored functions, for example:

GRANT EXECUTE 
ON PROCEDURE CheckCredit 
TO bob@localhost;
Code language: SQL (Structured Query Language) (sql)

In this example, bob@localhost can execute the stored procedure CheckCredit in the current database.

Proxy user privileges allow one user to be a proxy for another. The proxy user gets all privileges of the proxied user. For example:

GRANT PROXY 
ON root 
TO alice@localhost;
Code language: SQL (Structured Query Language) (sql)

In this example, alice@localhost assumes all privileges of root.

Finally, specify the account name of the user that you want to grant privileges after the TO keyword.

Notice that in order to use the GRANT statement, you must have the GRANT OPTION privilege and the privileges that you are granting. If the read_only system variable is enabled, you need to have the SUPER privilege to execute the GRANT statement.

MySQL GRANT statement examples

Typically, you use the CREATE USER statement to create a new user account first and then use the GRANT statement to grant privileges to the user.

First, create a new user called super@localhost by using the following CREATE USER statement:

CREATE USER super@localhost 
IDENTIFIED BY 'Secure1Pass!';
Code language: SQL (Structured Query Language) (sql)

Second, show the privileges assigned to super@localhost user by using the SHOW GRANTS statement.

SHOW GRANTS FOR super@localhost;
Code language: SQL (Structured Query Language) (sql)

The USAGE means that the super@localhost can log in the database but has no privilege.

Third, grant all privileges in all databases in the current database server to super@localhost:

GRANT ALL 
ON classicmodels.* 
TO super@localhost;
Code language: SQL (Structured Query Language) (sql)

Fourth, use the SHOW GRANTS statement again:

SHOW GRANTS FOR super@localhost;
Code language: SQL (Structured Query Language) (sql)

Permissible privileges for GRANT statement

The following table illustrates all permissible privileges that you can use for the GRANT and REVOKE statement:

In this tutorial, you have learned how to use the MySQL GRANT statement to grant privileges to a user.

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