months_between

Returns the number of months from "date_expression1" to "date_expression2". If "date_expression1" is later than "date_expression2" then the result will be a positive number. The days and time portions of the difference are ignored, i.e., the months are not rounded, except if "date_expression1" and "date_expression2" are the last days of a month.

months_between ( date_expression1 , date_expression2 )