Date Functions

• MONTHS_BETWEEN : NUmber of months between two dates
  MONTHS_BETWEEN(date1,date2)
  The result canbe positive or negative
  
• ADD_MONTHS : Add calendar months to date
  ADD_MONTHS(date, n)
  "n" must be an integer and can be negative
  
• NEXT_DAY : Next day of the date specified
  NEXT_DAY(date, 'char')
  The value of char must be a number representing a day or a character string.
  
• LAST_DAY : Last day of the month
  LAST_DAY(date) : Find s the date of the last day of the month that contains date
  
• ROUND : Round Date
  ROUND(date[,'fmt']) fmt ==> format model
  
• TRUNC : Truncate date
  TRUNC(date[,'fmt']) fmt ==> format model