Oracle 相当于 SQL Server DATEPART
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Oracle equivalent to SQL Server DATEPART
提问by Raj More
We need to get the HOUR out of a DATETIME column (expecting values from 0 to 23 to be returned).
我们需要从 DATETIME 列中获取 HOUR（期望返回 0 到 23 之间的值）。
Is there an Oracle equivalent of the SQL Server DATEPART function?
是否有与 SQL Server DATEPART 函数等效的 Oracle？
回答by a_horse_with_no_name
An alternative is the EXTRACT function which is an ANSI standard and also works on other DBMS, but it also requires the use of current_timestamp (also ANSI) instead of sysdate
另一种选择是 EXTRACT 函数，它是 ANSI 标准，也适用于其他 DBMS，但它也需要使用 current_timestamp（也是 ANSI）而不是 sysdate
SELECT extract(hour from current_timestamp)
FROM dual
回答by Michael Pakhantsov
SELECT to_number(to_char(sysdate, 'HH24')) FROM DUAL
回答by Ranjith M R
I think this is what you are looking for
我想这就是你要找的
select to_char(current_timestamp,'HH24') from dual;
回答by psaraj12
for additional ways of using DATEPART kind of function in oracle
有关在 oracle 中使用 DATEPART 类型函数的其他方法
DATEPART:-Weekday
日期部分：-工作日
--This would give the day for the week for a reference start day
--这将给出一周的日期作为参考开始日
DECLARE
Start_day date:=to_date('30-03-2012','DD-MM-YYYY');
check_date DATE:=SYSDATE;
Day_of_week NUMBER;
i NUMBER;
BEGIN
i:=to_char(Start_day,'D');
day_of_week:=mod((to_char(check_date,'D') -(i-1)+7),7);
if day_of_week=0
THEN
day_of_week:=7;
end if;
dbms_output.put_line(day_of_week);
END;
回答by Alvaro
if you want to get the month name of a date
如果您想获取日期的月份名称
select to_char( 'month', sysdate())
