HOUR - MaxCompute - Alibaba Cloud Documentation Center

Returns the hour component of a date value.

Syntax

int hour(datetime|timestamp|string <date>)

Parameters

date: required. A date value of the DATETIME, TIMESTAMP, or STRING type. The date value is in the yyyy-mm-dd hh:mi:ss or yyyy-mm-dd hh:mi:ss.ff3 format. If the value is of the STRING type, the value must include at least the hh:mi:ss part and cannot contain extra strings. This function is an additional function of MaxCompute V2.0.

Return value

A value of the INT type is returned. The return value varies based on the following rules:

If the value of date is not of the DATETIME, TIMESTAMP, or STRING type or the format does not meet the requirements, null is returned.
If the value of date is null, null is returned.
If the hour, minute, or second part in the value of date in the HOUR function exceeds the maximum value that is allowed in the 24-hour clock, the system automatically carries the digit. The maximum value that is allowed in the 24-hour clock is 24 for the hour part, 59 for the minute part, and 59 for the second part. For example, the return result of the select hour('25:59:60'); function is 2.

Sample data

This section provides sample source data for you to understand how to use date functions. In this topic, a table named mf_date_fun_t is created and data is inserted into the table. Sample statements:

create table if not exists mf_date_fun_t(
    id      int,
    date1   date,
    datetime1   datetime,
    timestamp1 timestamp,
    date2   date,
    datetime2   datetime,
    timestamp2 timestamp,
    date3 string,
    date4 bigint);
insert into mf_date_fun_t values
(1,DATE'2021-11-29',DATETIME'2021-11-29 00:01:00',TIMESTAMP'2021-01-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-20',123456780),
(2,DATE'2021-11-28',DATETIME'2021-11-28 00:02:00',TIMESTAMP'2021-02-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-21',123456781),
(3,DATE'2021-11-27',DATETIME'2021-11-27 00:03:00',TIMESTAMP'2021-03-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-22',123456782),
(4,DATE'2021-11-26',DATETIME'2021-11-26 00:04:00',TIMESTAMP'2021-04-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-23',123456783),
(5,DATE'2021-11-25',DATETIME'2021-11-25 00:05:00',TIMESTAMP'2021-05-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-24',123456784),
(6,DATE'2021-11-24',DATETIME'2021-11-24 00:06:00',TIMESTAMP'2021-06-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-25',123456785),
(7,DATE'2021-11-23',DATETIME'2021-11-23 00:07:00',TIMESTAMP'2021-07-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-26',123456786),
(8,DATE'2021-11-22',DATETIME'2021-11-22 00:08:00',TIMESTAMP'2021-08-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-27',123456787),
(9,DATE'2021-11-21',DATETIME'2021-11-21 00:09:00',TIMESTAMP'2021-09-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-28',123456788),
(10,DATE'2021-11-20',DATETIME'2021-11-20 00:10:00',TIMESTAMP'2021-10-11 00:00:00.123456789',DATE'2021-10-29',DATETIME'2021-10-29 00:00:00',TIMESTAMP'2021-10-11 00:00:00.123456789','2021-11-29',123456789);

Query data from the mf_date_fun_t table. Sample statement:

select * from mf_date_fun_t;
-- The following result is returned: 
+------+-------+------------+------------+-------+------------+------------+-------+------------+
| id   | date1 | datetime1  | timestamp1 | date2 | datetime2  | timestamp2 | date3 | date4      |
+------+-------+------------+------------+-------+------------+------------+-------+------------+
| 1    | 2021-11-29 | 2021-11-29 00:01:00 | 2021-01-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-20 | 123456780  |
| 2    | 2021-11-28 | 2021-11-28 00:02:00 | 2021-02-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-21 | 123456781  |
| 3    | 2021-11-27 | 2021-11-27 00:03:00 | 2021-03-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-22 | 123456782  |
| 4    | 2021-11-26 | 2021-11-26 00:04:00 | 2021-04-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-23 | 123456783  |
| 5    | 2021-11-25 | 2021-11-25 00:05:00 | 2021-05-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-24 | 123456784  |
| 6    | 2021-11-24 | 2021-11-24 00:06:00 | 2021-06-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-25 | 123456785  |
| 7    | 2021-11-23 | 2021-11-23 00:07:00 | 2021-07-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-26 | 123456786  |
| 8    | 2021-11-22 | 2021-11-22 00:08:00 | 2021-08-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-27 | 123456787  |
| 9    | 2021-11-21 | 2021-11-21 00:09:00 | 2021-09-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-28 | 123456788  |
| 10   | 2021-11-20 | 2021-11-20 00:10:00 | 2021-10-11 00:00:00.123456789 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123456789 | 2021-11-29 | 123456789  |
+------+-------+------------+------------+-------+------------+------------+-------+------------+

Example: static data

-- The return value is 12. 
select hour('2014-09-01 12:00:00');
-- The return value is 12. 
select hour('12:00:00');
-- The return value is null. 
select hour('20140901120000');
-- The return value is null. 
select hour(null);

Example: table data

Obtain the hour components of date values in the datetime1 and timestamp1 columns. Data in Sample data is used in this example. Sample statements:

-- Enable the MaxCompute V2.0 data type edition. Commit this command along with the SQL statement. 
set odps.sql.type.system.odps2=true;
select datetime1, hour(datetime1) as datetime1_hour, timestamp1, hour(timestamp1) as timestamp1_hour from mf_date_fun_t;

The following result is returned:

+---------------------+----------------+-------------------------------+-----------------+
| datetime1           | datetime1_hour | timestamp1                    | timestamp1_hour |
+---------------------+----------------+-------------------------------+-----------------+
| 2021-11-29 00:01:00 | 0              | 2021-01-11 00:00:00.123456789 | 0               |
| 2021-11-28 00:02:00 | 0              | 2021-02-11 00:00:00.123456789 | 0               |
| 2021-11-27 00:03:00 | 0              | 2021-03-11 00:00:00.123456789 | 0               |
| 2021-11-26 00:04:00 | 0              | 2021-04-11 00:00:00.123456789 | 0               |
| 2021-11-25 00:05:00 | 0              | 2021-05-11 00:00:00.123456789 | 0               |
| 2021-11-24 00:06:00 | 0              | 2021-06-11 00:00:00.123456789 | 0               |
| 2021-11-23 00:07:00 | 0              | 2021-07-11 00:00:00.123456789 | 0               |
| 2021-11-22 00:08:00 | 0              | 2021-08-11 00:00:00.123456789 | 0               |
| 2021-11-21 00:09:00 | 0              | 2021-09-11 00:00:00.123456789 | 0               |
| 2021-11-20 00:10:00 | 0              | 2021-10-11 00:00:00.123456789 | 0               |
+---------------------+----------------+-------------------------------+-----------------+

Related functions

HOUR is a date function. For more information about functions related to date computing and conversion, see Date functions.