Oracle 11g SQL Fundamentals 03--Date manipulation function

1, Oracle date in the internal representation is numeric format, precision from century to seconds.

2. The default date representation format is DD-MON-RR (not yy)

The difference between YY and RR:

3. Date Operation function

Example:

The second parameter of Next_day can also be a number that represents a date after a few days. Last_day is the last day of the month in which the date was asked.

ROUND (' dd-11-2014 ', ' month ') is accurate to the month, ' Day ' 1-15 counts this month's (' 01-11-2014 '), more than 15th is counted next month (' 01-12-2014 ').

ROUND (' dd-mon-2014 ', ' year ') is accurate to years, ' month ' 1-6 months counted this year's (' dd-mon-2014 '), 6-12 months counted for the next year (' dd-mon-2015 ').

Oracle 11g SQL Fundamentals 03--Date manipulation function