返回日期date位于那一年的第几周。周一作为一周的第一天。
注意事项
这一周算上一年还是下一年，取决于这一周的大多数日期（4天以上）在哪一年。算在前一年，就是前一年的最后一周；算在后一年就是后一年的第一周。
命令格式
bigint weekofyear (datetime <date>)参数说明
date：必填。DATETIME类型日期值。格式为yyyy-mm-dd hh:mi:ss。如果输入为STRING类型，且MaxCompute项目的数据类型版本是1.0，则会隐式转换为DATETIME类型后参与运算。
返回值说明
返回BIGINT类型。返回规则如下：
date非DATETIME或STRING类型，或格式不符合要求时，返回NULL。
date值为NULL时，返回NULL。
示例数据
为便于理解各函数的使用方法，本文为您提供源数据，基于源数据提供函数相关示例。创建表mf_date_fun_t，并添加数据，命令示例如下。
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);查询表mf_date_fun_t中的数据，命令示例如下：
select * from mf_date_fun_t;
--返回结果。
+------------+------------+---------------------+-------------------------+------------+---------------------+-------------------------+------------+------------+
| id | date1 | datetime1 | timestamp1 | date2 | datetime2 | timestamp2 | date3 | date4 |
+------------+------------+---------------------+-------------------------+------------+---------------------+-------------------------+------------+------------+
| 1 | 2021-11-29 | 2021-11-29 00:01:00 | 2021-01-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-20 | 123456780 |
| 2 | 2021-11-28 | 2021-11-28 00:02:00 | 2021-02-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-21 | 123456781 |
| 3 | 2021-11-27 | 2021-11-27 00:03:00 | 2021-03-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-22 | 123456782 |
| 4 | 2021-11-26 | 2021-11-26 00:04:00 | 2021-04-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-23 | 123456783 |
| 5 | 2021-11-25 | 2021-11-25 00:05:00 | 2021-05-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-24 | 123456784 |
| 6 | 2021-11-24 | 2021-11-24 00:06:00 | 2021-06-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-25 | 123456785 |
| 7 | 2021-11-23 | 2021-11-23 00:07:00 | 2021-07-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-26 | 123456786 |
| 8 | 2021-11-22 | 2021-11-22 00:08:00 | 2021-08-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-27 | 123456787 |
| 9 | 2021-11-21 | 2021-11-21 00:09:00 | 2021-09-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-28 | 123456788 |
| 10 | 2021-11-20 | 2021-11-20 00:10:00 | 2021-10-11 00:00:00.123 | 2021-10-29 | 2021-10-29 00:00:00 | 2021-10-11 00:00:00.123 | 2021-11-29 | 123456789 |
+------------+------------+---------------------+-------------------------+------------+---------------------+-------------------------+------------+------------+使用示例：静态数据示例
--返回1。虽然20141229属于2014年，但是这一周的大多数日期是在2015年，因此返回结果为1，表示是2015年的第一周。
select weekofyear(to_date("20141229", "yyyymmdd"));
--返回1。
select weekofyear(to_date("20141231", "yyyymmdd"));
--返回53。
select weekofyear(to_date("20151229", "yyyymmdd"));
--返回48。
set odps.sql.type.system.odps2=false;
select weekofyear('2021-11-29 00:01:00');
--返回NULL。
select weekofyear('20141231');
--返回NULL。
select weekofyear(null);使用示例：表数据示例
基于示例数据，计算datetime1列日期为所在年的第几周，命令示例如下。
select datetime1, weekofyear(datetime1) as datetime1_weekofyear from mf_date_fun_t;返回结果如下。
+---------------------+----------------------+
| datetime1 | datetime1_weekofyear |
+---------------------+----------------------+
| 2021-11-29 00:01:00 | 48 |
| 2021-11-28 00:02:00 | 47 |
| 2021-11-27 00:03:00 | 47 |
| 2021-11-26 00:04:00 | 47 |
| 2021-11-25 00:05:00 | 47 |
| 2021-11-24 00:06:00 | 47 |
| 2021-11-23 00:07:00 | 47 |
| 2021-11-22 00:08:00 | 47 |
| 2021-11-21 00:09:00 | 46 |
| 2021-11-20 00:10:00 | 46 |
+---------------------+----------------------+相关函数
WEEKOFYEAR函数属于日期函数，更多日期计算、日期转换的相关函数请参见日期函数。