Additional Support for Cross-Century Dates

The default date display format is MM/DD/CCYY, where MM is the month; DD is the day of the month; CC is the first two digits of a 4-digit year, indicating the century; and YY is the last two digits of a 4-digit year.

For example:

02/11/1999

For a table that fully describes the display of a date based on the specified format and user input, see the Describing Data manual.

The following date display options are available:

• You can display a row of data, even though it contains an invalid date field, using the command SET ALLOWCVTERR. The invalid date field is returned as the base date or as blanks, depending on other settings. For details, see your documentation on the SET command. This feature applies to non-FOCUS data sources when converting from the way data is stored (ACTUAL attribute) to the way it is formatted (FORMAT or USAGE attribute).
• If a date format field contains the value zero (0), you can display its base date using the command SET DATEDISPLAY = ON. By default, the value zero in a date format field such as YYMD is returned as a blank. For details, see Customizing Your Environment.
• You can display the current date with a 4-digit year using the Dialogue Manager system variables &YYMD, &MDYY, and &DMYY. The system variable &DATEfmt displays the current date as specified by the value of fmt, which is a combination of allowable date options, including a 4-digit year (for example, &DATEYYMD). For details, see Managing Flow of Control in an Application.

You can temporarily alter the system date for application testing and debugging using the command SET TESTDATE. With this feature, you can simulate clock settings beyond the year 1999 to determine the way your program will behave. For details, see Customizing Your Environment.

The date functions supplied with your software work across centuries. Many of them facilitate date manipulation. For details, see the Using Functions manual.

You can convert a legacy date to a date format in a FOCUS data source using the option DATE NEW on the REBUILD command. For details, see the Maintaining Databases manual.

The ALL option, in conjunction with the HOLD option, on the CHECK FILE command includes file-level and field-level default century and year thresholds as specified in a Master File. For details, see the Describing Data manual.

The year in the time stamp for a FOCUS data source is physically written to page one of the file in the format CCYY.