| << Click to Display Table of Contents >> 日期时间函数 |     | 
永洪产品提供了多种日期函数。请参见日期函数的语法表 。
此外,许多日期函数还使用 date_part,它是一个常量字符串参数。
有效 date_part 值为:
| DATE_PART | 值 | 
|---|---|
| year | 四位数年份 | 
| quarter | 1-4 | 
| month | 1-12 或 "January"、"February" 等 | 
| hour | 0-23 | 
| minute | 0-59 | 
| second | 0-59 | 
| dayofyear | 一年中的第几天;1 月 1 日为 1、2 月 1 日为 32,依此类推 | 
| dayofmonth | 1-31 | 
| dayofweek | 1-7 或 "Sunday"、"Monday" 等 | 
| weekofyear | 1-52 | 
| 函数 | 语法 | 说明 | 举例 | 
|---|---|---|---|
| date | date(year, month, day) | 通过数字生成日期值 | 例如: date(2020,11,3) = 2020-11-03 | 
| dateAdd | dateAdd(date,date_part, interval) | 返回指定日期,该日期的指定 date_part中添加了指定的数字 interval,date_part的可选值为"year", "quarter", "month", "weekofyear","dayofyear", "dayofmonth","dayofweek", "hour", "minute", "second" | 例如: dateAdd(col['order_date'],'month', 3) 该表达式会向订单日期添加三个月 | 
| dateGap | dateGap(date1,date2, date_option) 
 
 | 比较两个日期按照date_option的差值。date_option的参数有:year,quarter,month,weekofyear,dayofyear,dayofmonth,dayofweek,hour,minute,second | 例如: 假如col['order_date'] 是 2010-04-13,col['receive_date'] 是 2010-04-19 dateGap(col['order_date'], col['receive_date'], 'month') = 0 dateGap(col['order_date'], col['receive_date'], 'dayofmonth') = 6 | 
| dateName | dateName(date, date_part, [start_of_week]) | 返回日期的指定 date_part 的名称,date_part的可选值为"year","quarter","month", "weekofyear","dayofyear", "dayofmonth","dayofweek", "hour","minute","second",start_of_week的可选值为"monday","tuesday","wednesday","thursday","friday","saturday", "sunday"。如果省略不写start_of_week,则周的起始日是由数据源的配置决定 | 例如: 假如时间是2021-04-25 18:30:00,则dateName(col['order_date'], 'Monday')=4 | 
| datePart | datePart(date,date_part) 
 | 以整数的形式返回date的 date_part date_part的可选值为"year", "quarter", "month", "weekofyear", "dayofyear", "dayofmonth", "dayofweek", "hour", "minute", "second" | 例如: 假如col['order_date'] 是 2010-04-13 datePart(col['order_date'], 'year') = 2010 datePart(col['order_date'], 'month') = 4 | 
| dateTrunc | dateTrunc(date_part, date, [start_of_week]) 
 
 | 按 date_part 指定的准确度截断指定日期 date_part的可选值为"year", "quarter", "month", "weekofyear", "dayofyear", "dayofmonth", "dayofweek", "hour", "minute", "second" start_of_week 可选参数,可选值为"monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday" | 例如: 假如col['order_date'] 是 2010-05-13 18:30:00 dateTrunc('quarter', col['order_date']) = 2010-04-01 00:00:00 dateTrunc('month', col['order_date']) = 2010-05-01 00:00:00 | 
| dateValue | dateValue(date) | 
 返回到起始日期的天数,1900-01-01返回的是0 
 | 例如: 假如col['order_date'] 是 2020-02-17 。 dateValue(col['order_date']) = 43876 | 
| day | day(date) | 
 返回的是这个月的天数,值范围[1, 31] 
 | 例如: 假如col['order_date'] 是 2010-04-13 day(col['order_date']) = 13 | 
| getDate | getDate(date) | 检测输入的参数是否是日期类型的,是返回参数,否返回null | 例如: getDate(col['order_date']) | 
| isDate | isDate(date) | 检测输入的值或者列是否是日期类型的,返回true或者false | 例如: isDate(col['order_date']) | 
| month | month(date) | 返回的月的数字表示,值范围[1, 12] | 例如: 假如col['order_date'] 是 2010-04-13 month(col['order_date']) = 4 | 
| now | now() | 返回服务器时间 | 例如: now() = 2020-02-17 16:08:21 | 
| quarter | quarter(date) | 返回季度的数字表示,值范围[1, 4] | 例如: 假如col['order_date'] 是 2010-04-13 quarter(col['order_date']) = 2 | 
| today | 
 today() 
 | 返回服务器日期 | 例如: today() = 2020-02-17 | 
| weekday | weekday(date, [return_type]) | 返回星期几的数字表示return_type 可选参数,如果设置值为数字1 或省略 则返回的值1 至7, 代表星期天到星期六;设置的数字是2 则返回的值为1 至7 ,代表星期一到星期天;如果设置的值为数字3,则返回的值为0至6,代表星期一到星期天 | 例如: 假如col['order_date'] 是 2020-02-17 weekday(col['order_date']) = 2 | 
| weekNum | weekNum(date, [dayType]) | 返回一年内的周数,dayType不传或者传2表示周一为一周的开始 | 例如: 假如col['order_date'] 是 2020-02-17 weekNum(col['order_date']) = 8 | 
| year | year(date) | 返回年的数字表示 | 例如: 假如col['order_date'] 是 2010-04-13 。 year(col['order_date']) = 2010 |