計算日期值增加指定月數後的日期。此函數為MaxCompute 2.0擴充函數。
命令格式
string add_months(date|datetime|timestamp|string <startdate>, int <num_months>)
參數說明
startdate:必填。DATE、DATETIME、TIMESTAMP或STRING類型,格式為
yyyy-mm-dd
、yyyy-mm-dd hh:mi:ss
或yyyy-mm-dd hh:mi:ss.ff3
。取值為STRING類型格式時,至少要包含yyyy-mm-dd
且不含多餘的字串。num_months:必填。INT型數值。
傳回值說明
返回開始日期startdate增加num_months個月後的日期,返回STRING類型的日期值,格式為yyyy-mm-dd
。返回規則如下:
startdate非DATE、DATETIME、TIMESTAMP或STRING類型,或格式不符合要求時,返回NULL。
startdate值為NULL時,返回報錯。
num_months值為NULL時,返回NULL。
樣本資料
為便於理解各函數的使用方法,本文為您提供來源資料,基於來源資料提供函數相關樣本。建立表mf_date_fun_t,並添加資料,命令樣本如下。
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);
查詢表mf_date_fun_t中的資料,命令樣本如下:
select * from mf_date_fun_t;
--返回結果。
+------+-------+------------+------------+-------+------------+------------+-------+------------+
| 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 |
+------+-------+------------+------------+-------+------------+------------+-------+------------+
使用樣本:待用資料樣本
--返回2017-05-14。
select add_months('2017-02-14',3);
--返回2017-05-14。
select add_months('2017-2-14',3);
--返回2017-05-14。
select add_months('2017-02-14 21:30:00',3);
--返回NULL。
select add_months('20170214',3);
--返回NULL。
select add_months('2017-02-14 21:30:00',null);
使用樣本:表資料樣本
基於樣本資料,將date1、datetime1、timestamp1和date3列日期轉換為整型的UNIX格式的日期值,命令樣本如下。
--開啟2.0新類型。此命令需要與SQL語句一起提交。
set odps.sql.type.system.odps2=true;
select date1, add_months(date1,1) as date1_add_months, datetime1, add_months(datetime1, 2) as datetime1_add_months, timestamp1, add_months(timestamp1,3) as timestamp1_add_months, date3, add_months(date3,4) as date3_add_months from mf_date_fun_t;
返回結果如下。
+------------+------------------+---------------------+----------------------+-------------------------------+-----------------------+------------+------------------+
| date1 | date1_add_months | datetime1 | datetime1_add_months | timestamp1 | timestamp1_add_months | date3 | date3_add_months |
+------------+------------------+---------------------+----------------------+-------------------------------+-----------------------+------------+------------------+
| 2021-11-29 | 2021-12-29 | 2021-11-29 00:01:00 | 2022-01-29 | 2021-01-11 00:00:00.123456789 | 2021-04-11 | 2021-11-20 | 2022-03-20 |
| 2021-11-28 | 2021-12-28 | 2021-11-28 00:02:00 | 2022-01-28 | 2021-02-11 00:00:00.123456789 | 2021-05-11 | 2021-11-21 | 2022-03-21 |
| 2021-11-27 | 2021-12-27 | 2021-11-27 00:03:00 | 2022-01-27 | 2021-03-11 00:00:00.123456789 | 2021-06-11 | 2021-11-22 | 2022-03-22 |
| 2021-11-26 | 2021-12-26 | 2021-11-26 00:04:00 | 2022-01-26 | 2021-04-11 00:00:00.123456789 | 2021-07-11 | 2021-11-23 | 2022-03-23 |
| 2021-11-25 | 2021-12-25 | 2021-11-25 00:05:00 | 2022-01-25 | 2021-05-11 00:00:00.123456789 | 2021-08-11 | 2021-11-24 | 2022-03-24 |
| 2021-11-24 | 2021-12-24 | 2021-11-24 00:06:00 | 2022-01-24 | 2021-06-11 00:00:00.123456789 | 2021-09-11 | 2021-11-25 | 2022-03-25 |
| 2021-11-23 | 2021-12-23 | 2021-11-23 00:07:00 | 2022-01-23 | 2021-07-11 00:00:00.123456789 | 2021-10-11 | 2021-11-26 | 2022-03-26 |
| 2021-11-22 | 2021-12-22 | 2021-11-22 00:08:00 | 2022-01-22 | 2021-08-11 00:00:00.123456789 | 2021-11-11 | 2021-11-27 | 2022-03-27 |
| 2021-11-21 | 2021-12-21 | 2021-11-21 00:09:00 | 2022-01-21 | 2021-09-11 00:00:00.123456789 | 2021-12-11 | 2021-11-28 | 2022-03-28 |
| 2021-11-20 | 2021-12-20 | 2021-11-20 00:10:00 | 2022-01-20 | 2021-10-11 00:00:00.123456789 | 2022-01-11 | 2021-11-29 | 2022-03-29 |
+------------+------------------+---------------------+----------------------+-------------------------------+-----------------------+------------+------------------+
相關函數
ADD_MONTHS函數屬於日期函數,更多日期計算、日期轉換的相關函數請參見日期函數。