Teradata中的日期/時間計算

Question

請幫助我在Teradata中計算一天的開始，一天的結束，月份的開始，月份的結束（以及最多3個時間）。 我想要這樣的東西'2014-03-01 00：00：00.000'; 謝謝

Answer 1

這應該使您開始：

SELECT DATE
     , CAST(DATE AS INTEGER) AS DateInteger
     , CAST(((DATE / 100) * 100) + 1 AS DATE) AS MonthBegin
     , CAST((((DATE / 100) +1 ) * 100) + 1 AS DATE) AS NextMonthBegin
     , CAST((((DATE / 100) +1 ) * 100) + 1 AS DATE)  - 1 AS MonthEnd
     , CURRENT_TIMESTAMP(3)
     , CAST(CAST(CURRENT_TIMESTAMP(3) AS DATE) AS TIMESTAMP(3)) AS DayBegin
     , CAST((CAST(CURRENT_TIMESTAMP(3) AS DATE) + 1) AS TIMESTAMP(3)) - INTERVAL '0.001' SECOND AS DayEnd

*編輯*

SELECT CURRENT_DATE
     , CURRENT_DATE - EXTRACT( DAY FROM CURRENT_DATE) + 1 as MonthBegin
     , ADD_MONTHS(( CURRENT_DATE - EXTRACT (DAY FROM CURRENT_DATE) + 1), 1) as NextMonthBegin
     , ADD_MONTHS(( CURRENT_DATE - EXTRACT (DAY FROM CURRENT_DATE) + 1), 1) - 1 as MonthEnd
     , CURRENT_TIMESTAMP(3)
     , CAST( CAST(CURRENT_TIMESTAMP (3) AS DATE) AS TIMESTAMP (3)) AS DayBegin
     , CAST(( CAST(CURRENT_TIMESTAMP (3) AS DATE) + 1) AS TIMESTAMP (3)) - INTERVAL '0.001' SECOND AS DayEnd;

從這里應該可以將時間戳記為“月開始”，“月結束”和“下個月開始”。 讓我知道您是否被卡住。