Overview of Date Functions

The following explains the difference between the types of date functions:

Date formats have an internal representation matching either numeric or alphanumeric format. For example, A6MDY matches alphanumeric format, YYMD and I6DMY match numeric format. When function output is a date in specified by output, it can be used either for assignment to another date field of this format, or it can be used for further data manipulation in the expression with data of matching formats. Assignment to another field of a different date format, will yield a random result.

In addition to the functions discussed in this topic, there are date and time functions that are available only in the Maintain language. For information on these functions, see Maintain-specific Date and Time Functions.

For many functions, the output argument can be supplied either as a field name or as a format enclosed in single quotation marks. However, if a function is called from a Dialogue Manager command, this argument must always be supplied as a format, and if a function is called from a Maintain procedure, this argument must always be supplied as a field name. For detailed information about calling a function and supplying arguments, see Accessing and Calling a Function.