DAY-MaxCompute(MaxCompute)-阿里云帮助中心

Returns the day of the month from a date value.

DAY is an additional function introduced in MaxCompute V2.0.

Syntax

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

Parameters

date (required): A date value of the DATETIME, TIMESTAMP, DATE, or STRING type.

Accepted formats:

Format	Example
`yyyy-mm-dd`	`2014-09-01`
`yyyy-mm-dd hh:mi:ss`	`2014-09-01 00:00:00`
`yyyy-mm-dd hh:mi:ss.ff3`	`2014-09-01 00:00:00.000`

For STRING input, the value must include at least the yyyy-mm-dd part and must not contain extra characters.

Return value

Returns an INT value representing the day of the month.

Returns null if:

The date value is not of the DATETIME, TIMESTAMP, DATE, or STRING type, or the format does not meet the requirements.
The date value is null.

Examples

Simple examples

-- Returns 1
select day('2014-09-01');

-- Returns null (format does not meet requirements)
select day('20140901');

-- Returns null
select day(null);

Table-based examples

The following example uses the mf_date_fun_t table. Run the setup statements first if the table does not exist.

Set up 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);

Query the table

Extract the day of the month from date1, datetime1, timestamp1, and date3:

-- Enable the MaxCompute V2.0 data type edition.
-- Submit this SET statement with the SQL statement.
set odps.sql.type.system.odps2=true;
select
    date1, day(date1) as date1_day,
    datetime1, day(datetime1) as datetime1_day,
    timestamp1, day(timestamp1) as timestamp1_day,
    date3, day(date3) as date3_day
from mf_date_fun_t;

The following result is returned:

+------------+-----------+---------------------+---------------+-------------------------------+----------------+------------+-----------+
| date1      | date1_day | datetime1           | datetime1_day | timestamp1                    | timestamp1_day | date3      | date3_day |
+------------+-----------+---------------------+---------------+-------------------------------+----------------+------------+-----------+
| 2021-11-29 | 29        | 2021-11-29 00:01:00 | 29            | 2021-01-11 00:00:00.123456789 | 11             | 2021-11-20 | 20        |
| 2021-11-28 | 28        | 2021-11-28 00:02:00 | 28            | 2021-02-11 00:00:00.123456789 | 11             | 2021-11-21 | 21        |
| 2021-11-27 | 27        | 2021-11-27 00:03:00 | 27            | 2021-03-11 00:00:00.123456789 | 11             | 2021-11-22 | 22        |
| 2021-11-26 | 26        | 2021-11-26 00:04:00 | 26            | 2021-04-11 00:00:00.123456789 | 11             | 2021-11-23 | 23        |
| 2021-11-25 | 25        | 2021-11-25 00:05:00 | 25            | 2021-05-11 00:00:00.123456789 | 11             | 2021-11-24 | 24        |
| 2021-11-24 | 24        | 2021-11-24 00:06:00 | 24            | 2021-06-11 00:00:00.123456789 | 11             | 2021-11-25 | 25        |
| 2021-11-23 | 23        | 2021-11-23 00:07:00 | 23            | 2021-07-11 00:00:00.123456789 | 11             | 2021-11-26 | 26        |
| 2021-11-22 | 22        | 2021-11-22 00:08:00 | 22            | 2021-08-11 00:00:00.123456789 | 11             | 2021-11-27 | 27        |
| 2021-11-21 | 21        | 2021-11-21 00:09:00 | 21            | 2021-09-11 00:00:00.123456789 | 11             | 2021-11-28 | 28        |
| 2021-11-20 | 20        | 2021-11-20 00:10:00 | 20            | 2021-10-11 00:00:00.123456789 | 11             | 2021-11-29 | 29        |
+------------+-----------+---------------------+---------------+-------------------------------+----------------+------------+-----------+