Date and time functions manipulate date and time values. There are two types of date and time functions:

• Standard date and time functions for use with non-legacy dates. For details, see Using Standard Date and Time Functions.
• Legacy date functions for use with legacy dates. For more information, see Using Legacy Date Functions.

  If a date is in an alphanumeric or numeric field that contains date display options (for example, I6YMD), you must use the legacy date functions.