HOUR-MaxCompute(MaxCompute)-阿里云帮助中心

Extracts the hour component from a DATETIME, TIMESTAMP, or STRING value and returns it as an INT.

HOUR is a MaxCompute V2.0 additional function.

Syntax

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

Parameters

Parameter	Required	Type	Format
`date`	Yes	DATETIME, TIMESTAMP, or STRING	`yyyy-mm-dd hh:mi:ss` or `yyyy-mm-dd hh:mi:ss.ff3`

For STRING values, the input must include at least the hh:mi:ss part and must not contain extra characters outside the supported formats.

Return value

Returns an INT. Returns null in the following cases:

The input is null.
The input type is not DATETIME, TIMESTAMP, or STRING.
The STRING input does not match the required format.

Overflow behavior: If the hour, minute, or second part exceeds the 24-hour clock maximum (24 for hours, 59 for minutes, 59 for seconds), the system carries the overflow into the next unit. For example, hour('25:59:60') returns 2.

Examples

Static values

select hour('2014-09-01 12:00:00');  -- Returns 12
select hour('12:00:00');             -- Returns 12
select hour('20140901120000');       -- Returns null (unsupported format)
select hour(null);                   -- Returns null

Table data

The following example uses the sample table mf_date_fun_t. For the table definition and sample data, see Sample data.

Enable the MaxCompute V2.0 data type edition, then run the query. Submit both statements together.

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;

Result:

+---------------------+----------------+-------------------------------+-----------------+
| 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               |
+---------------------+----------------+-------------------------------+-----------------+

All hour values are 0 because the datetime1 timestamps range from 00:01 to 00:10 and the timestamp1 timestamps all start at 00:00.

Sample data

The examples in this topic use the table mf_date_fun_t. Run the following statements to create the table and insert sample data:

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);

To verify the data was inserted correctly:

select * from mf_date_fun_t;

Expected output:

+------+------------+---------------------+-------------------------------+------------+---------------------+-------------------------------+------------+------------+
| 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  |
+------+------------+---------------------+-------------------------------+------------+---------------------+-------------------------------+------------+------------+

Related functions

HOUR is a date function. For other date computing and conversion functions, see Date functions.