I think that if the date is not valid, such as a year-month that we are implying from your example, then you must choose then to make the date a NULL (invalid), or if it is a circa date, you must complete it with a day.On the other hand, if it is a JULIAN date, you need to do this (copied from <a href="http://www.ehow.com/how_12073756_convert-julian-date-sql.html):CREATE">http://www.ehow.com/how_12073756_convert-julian-date-sql.html):CREATE</a> FUNCTION convert_julian_to_dateti