Bii o ṣe le ṣe afikun ati yọ awọn ọjọ ati awọn akoko ninu MySQL

Itọkasi

DATE_ADD ati DATE_SUB

Awọn iṣẹ meji wọnyi jẹ bata, ọkan jẹ afikun ati ekeji jẹ iyokuro. Iṣẹ wọn ni lati ṣafikun tabi iyokuro akoko kan lati ọjọ ti a ṣalaye. Fun lilo ni pato, tọka si apẹẹrẹ atẹle. Ninu apẹẹrẹ akọkọ, a ṣafikun oṣu kan si akoko lọwọlọwọ, ati pe ekeji yọkuro oṣu kan lati akoko lọwọlọwọ.

            SELECT DATE_ADD(now(), INTERVAL 1 MONTH);
SELECT DATE_SUB(now(), INTERVAL 1 MONTH);
        

ADDDATE ati SUBDATE

Awọn iṣẹ meji wọnyi tun jẹ bata, ọkan jẹ afikun ati ekeji jẹ iyokuro. Lilo wọn jẹ kanna bii DATE_ADD ati DATE_SUB. Fun lilo ni pato, tọka si apẹẹrẹ atẹle. Ninu apẹẹrẹ akọkọ, a ṣafikun oṣu kan si akoko lọwọlọwọ, ati pe ekeji yọkuro oṣu kan lati akoko lọwọlọwọ.

            SELECT ADDDATE(now(), INTERVAL 1 MONTH);
SELECT SUBDATE(now(), INTERVAL 1 MONTH);
        

Lilo diẹ sii

A lo oṣu nikan bi paramita ninu apẹẹrẹ, sibẹsibẹ, wakati, iṣẹju, keji, ọsẹ, ọjọ, ọdun tun le ṣee lo bi awọn ipele, ati pe o tun le ṣe atilẹyin awọn iṣẹju ati iṣẹju-aaya, awọn wakati ati iṣẹju ati iṣẹju-aaya ati diẹ sii apapo. Fun awọn alaye, jọwọ tọka si atokọ ni isalẹ.

            MICROSECOND
SECOND
MINUTE
HOUR
DAY
WEEK
MONTH
QUARTER
YEAR
SECOND_MICROSECOND 'SECONDS.MICROSECONDS'
MINUTE_MICROSECOND 'MINUTES:SECONDS.MICROSECONDS'
MINUTE_SECOND 'MINUTES:SECONDS'
HOUR_MICROSECOND 'HOURS:MINUTES:SECONDS.MICROSECONDS'
HOUR_SECOND 'HOURS:MINUTES:SECONDS'
HOUR_MINUTE 'HOURS:MINUTES'
DAY_MICROSECOND 'DAYS HOURS:MINUTES:SECONDS.MICROSECONDS'
DAY_SECOND 'DAYS HOURS:MINUTES:SECONDS'
DAY_MINUTE 'DAYS HOURS:MINUTES'
DAY_HOUR 'DAYS HOURS'
YEAR_MONTH 'YEARS-MONTHS'
        

miiran alaye

Ni otitọ, iyokuro tun le lo DATE_ADD, a nilo lati kọ nikan paramita bi nọmba odi. Ni afikun, MariaDB jẹ ẹka ti MySQL, ati pe sintasi SQL wọn jẹ ipilẹ kanna, nitorinaa awọn iṣẹ mẹrin ti o wa loke wa lori MariaDB, ati pe lilo jẹ deede kanna.