sql - When and why does the TRUNC(DATE, [FORMAT]) used in the real world -


i getting oracle database. came across trunc(date, [fmt]) function. not clear on except seems return beginning value of sort?

can educate me on it? when or used @ work, or why might want use function?

another thing useful time component of current day. use expression time:

select sysdate - trunc(sysdate) todaystime dual

because system date stored in decimal format (e.g. sysdate = 42651.2426897456) , integer value corresponds midnight, can use above statement decimal portion (e.g. todaystime = 0.2426897456, or before 6 am).

there may easier ways this, in applications has been easiest need work day's time component.


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