DATEDIFF

语法

INT DATEDIFF(VARCHAR enddate, VARCHAR startdate)
INT DATEDIFF(TIMESTAMP enddate, VARCHAR startdate)
INT DATEDIFF(VARCHAR enddate, TIMESTAMP startdate)
INT DATEDIFF(TIMESTAMP enddate, TIMESTAMP startdate)

描述

DATEDIFF函数用于计算两个日期之间的天数差值。

约束与限制

本章节仅适用于MRS 3.6.0-LTS.1及之后版本。

入参

参数	数据类型
enddate	TIMESTAMP、VARCHAR
startdate	TIMESTAMP、VARCHAR

VARCHAR日期格式：yyyy-MM-dd或yyyy-MM-dd HH:mm:ss。
如果入参中任何一个为NULL，则返回为NULL。

示例

CREATE TABLE source (
  time1 TIMESTAMP
) WITH (
  'connector' = 'datagen',
  'rows-per-second' = '1'
);
create TABLE print with(
'connector' = 'print'
)as select 
DATEDIFF('2025-10-15 00:00:00', '2025-9-15 00:00:00') as int1, 
        DATEDIFF(time1 ,'2025-12-1 00:00:00') as int2, 
        DATEDIFF('2025-12-1',time1 ) as int3, 
        DATEDIFF(time1 ,CAST(null as VARCHAR)) as int4, 
        DATEDIFF(CAST(null as VARCHAR), '2025-12-1 00:00:00') as int5, 
        DATEDIFF(CAST(null as VARCHAR), time1 ) as int6, 
        DATEDIFF(time1 ,time1 )as int7
from source;