MariaDB HOUR() Function

In MariaDB, HOUR() is a built-in function that returns the hour part from a given time expression.

MariaDB HOUR() Syntax

This is the syntax of the MariaDB HOUR() function:

HOUR(time)

Parameters

time

Required. A time or datetime expression.

Return value

The MariaDB HOUR() function extracts the hour portion of the specified time or datetime and returns it as a number.

If there is no hour part in time, the HOUR() function will return 0.

If the argument is NULL, the HOUR() function will return NULL.

Because the maximum time supported by MySQL is 838:59:59, the maximum return value of the HOUR() function is 838.

MariaDB HOUR() Examples

This statement shows the usage of the MariaDB HOUR() function:

SELECT
    HOUR('10:10:10'),
    HOUR('2022-02-28 10:10:10'),
    HOUR('123:10:10'),
    HOUR('1234:10:10'),
    HOUR('2022-02-00'),
    HOUR('2022-02-30'),
    HOUR('Not A DATE'),
    HOUR(NULL)\G

Output:

           HOUR('10:10:10'): 10
HOUR('2022-02-28 10:10:10'): 10
          HOUR('123:10:10'): 123
         HOUR('1234:10:10'): 838
         HOUR('2022-02-00'): 0
         HOUR('2022-02-30'): 0
         HOUR('Not A DATE'): NULL
                 HOUR(NULL): NULL

In this example:

• HOUR('1234:10:10') returned 838, because 838 is the maximum time supported by MariaDB.
• Both HOUR('2022-02-00') and HOUR('2022-02-30') returned 0.
• If an illegal time expression or NULL is provided, the HOUR() function will return NULL.

Conclusion

In MariaDB, HOUR() is a built-in function that returns the hour part from a given time expression.