SQL Reference

HOUR(time)

time: This parameter represents the exact time value from which the hour is to be extracted. It accepts a string formatted as a time (e.g., ‘15

Example

SELECT HOUR('15:30:00') AS 'Hour';

Output

+------+
| Hour |
+------+
|  15  |
+------+

Explanation

The HOUR function in MySQL is used to get the hour from a time. In the example, input time ‘15:30:00’ was passed to the HOUR function, and this returned 15, which is the hour in the provided time.

HOUR(timestamp): integer

name: timestamp

Example

SELECT EXTRACT(HOUR FROM TIMESTAMP '2022-01-01 14:30:00');

Output

Explanation

The EXTRACT function in PostgreSQL is used to retrieve subfields such as year, month, day, hour, etc., from date/time columns. In the provided example, it extracts the hour from the timestamp ‘2022-01-01 14:30:00’, producing the number 14 as the result.

HOUR(expression)

expression: This parameter is the time value from which SQL server will extract the hour. It can be a time, date, smalldatetime, datetime, datetime2, or datetimeoffset. The expression will return the hour as an integer.

Example

DECLARE @date DATETIME;
SET @date = '01/01/2022 12:30:45';
SELECT HOUR(@date) AS 'Hour';

Output

Hour
----
12

Explanation

In the code, a date-time variable @date is declared and set to ‘01/01/2022 12:30:45’. The HOUR function is then used to extract and return the hour portion of the time in the @date variable. The output, 12, shows the hour extracted from the @date variable.

HOUR(date)

date: Represents the input date value from which the hour needs to be extracted. This parameter has to be in DATE or TIMESTAMP format. The function will return the hour component of the input date as an integer in 24-hour format ranging from 0 to 23.

Example

SELECT EXTRACT(HOUR FROM TO_DATE('2021-09-22 17:30:00', 'YYYY-MM-DD HH24:MI:SS')) AS HOUR FROM dual;

Output

Explanation

The EXTRACT function is used to get a specific part from a datetime. In this case, HOUR is extracted from the given datetime value. The date string ‘2021-09-22 17:30:00’ is converted to a date first using TO_DATE(). This SQL will return the hour from the provided date-time which is 17 in this case.

HOUR(date)

date: The parameter “date” is a string representing a date and time. The HOUR function extracts the hour from this date-time string as an integer ranging from 0 (representing 12

Example

SELECT strftime('%H', '2022-09-30 15:20:00') as 'Hour';

Output

Hour
----
15

Explanation

In the above code, the SQLite strftime('%H', '2022-09-30 15:20:00') function is used to extract the hour from the datetime string. The ‘%H’ format specifier is used to get the hour in 24-hour format. The result is ‘15’, which indicates the 15th hour of the day or 3 PM.