SQL Oracle 中 DATEADD() 的等效函数
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Equivalent function for DATEADD() in Oracle
提问by Geethu
I have to get a date that is 6 months from the system date in Oracle.
And I have to get it by running an open-query from SQL. DATEADD(MONTH,-6, GETDATE())function serves the purpose in SQL.
Does the function DATEADD(MONTH,-6, GETDATE())in SQL have an equivalentfunction in Oracle?
我必须得到一个距 Oracle 系统日期 6 个月的日期。
我必须通过从 SQL 运行开放查询来获取它。DATEADD(MONTH,-6, GETDATE())函数在 SQL 中起到作用。
请问功能DATEADD(MONTH,-6, GETDATE())在SQL有一个equivalent在Oracle中的功能？
回答by Maheswaran Ravisankar
Method1:ADD_MONTHS
方法 1：ADD_MONTHS
ADD_MONTHS(SYSDATE, -6)
ADD_MONTHS(SYSDATE, -6)
Method 2:Interval
方法二：间隔
SYSDATE - interval '6' month
SYSDATE - interval '6' month
Note:if you want to do the operations from start of the current month always, TRUNC(SYSDATE,'MONTH')would give that. And it expects a Datedatatype as input.
注意：如果您想始终从当月开始进行操作，请TRUNC(SYSDATE,'MONTH')给出。它需要一个Date数据类型作为输入。
回答by Papa Stahl
Not my answer:
不是我的回答：
I wasn't too happy with the answers above and some additional searching yielded this :
我对上面的答案不太满意，一些额外的搜索产生了这个：
SELECT SYSDATE AS current_date,
SYSDATE + 1 AS plus_1_day,
SYSDATE + 1/24 AS plus_1_hours,
SYSDATE + 1/24/60 AS plus_1_minutes,
SYSDATE + 1/24/60/60 AS plus_1_seconds
FROM dual;
which I found very helpful. From http://sqlbisam.blogspot.com/2014/01/add-date-interval-to-date-or-dateadd.html
我发现这很有帮助。来自http://sqlbisam.blogspot.com/2014/01/add-date-interval-to-date-or-dateadd.html
回答by hashbrown
Equivalent will be
等效将是
ADD_MONTHS( SYSDATE, -6 )
回答by cluelessgumshoe
--ORACLE SQL EXAMPLE
SELECT
SYSDATE
,TO_DATE(SUBSTR(LAST_DAY(ADD_MONTHS(SYSDATE, -1)),1,10),'YYYY-MM-DD')
FROM DUAL
