Maintain Date Aliases - CALF0420

Purpose

To enable the definition of a date alias, date alias offset or date alias pair.

Subsystem

Calendar

Structure

Three Blocks

Date Alias

Date Alias Offset

Date Alias Pair

Navigation Button invokes:

 

Maintain Date Alias Instances form

Maintain Date Alias Offset Constraints form

Maintain Offset Calendar Restrictions

Note: These buttons will display either a '+' or a '-' depending on whether an instance, constraint or calendar restriction exists for this Date Alias.

Image

 

Date Alias

Explanation

In the system, date alias is the generic name for a calendar event, not the actual occurrence of an event. It is defined by its name and the date alias category to which it is assigned. It may also be assigned to a calendar category which will limit its use exclusively to calendar instances of the same category.

Example

CENSUS could be the date alias for any day on which census data is collected for the government. There would be any number of census days over time, occurring on different dates each year.

Using this form to define a date alias is the first step to including the specific date of an event in the relevant calendar. By attaching a date to CENSUS, say 31/3/96, and applying it to a calendar instance, say semester 1, 1996 (SEM-1, 3/3/96, 15/6/96) we can define a particular occurrence of the date alias CENSUS and hence create a Date Alias Instance.

The Building a Calendar diagram illustrates this.

 

To create a new date alias, using the Maintain Date Aliases form:

  1. Enter Insert Mode.
    2.
  2. Enter the date alias name in the Date Alias field.
    3.
  3. Enter an abbreviated description of the date alias in the Abbreviation field.
    4.
  4. Enter a full description of the date alias in the Description field.
    5.
  5. Select a date alias category from the list of values in the Date Alias Category field.
    6.
  6. Enter any notes about this date alias in the Notes field. (optional)
    7.
  7. Select a calendar category from the list of values in the Calendar Category field. (optional)
    8.
  8. Save.

Rules:
  • Assigning a calendar category to a date alias will limit its use exclusively to calendar instances of the same calendar category.

To modify a date alias, using the Maintain Date Aliases form:

  1. Find the record to be modified.
    2.
  2. Modify the record as required.
    3.
  3. Save.

Rules:

  • If a date alias has been used by a date alias instance and applied to a calendar instance its calendar category cannot be modified.

To delete a date alias, using the Maintain Date Aliases form:

  1. Find the date alias to be deleted.
    2.
  2. Delete record.
    3.
  3. Save.

Rules:

  • A date alias cannot be deleted if it has been:
  • However, it can be closed, preventing any further use, by selecting the Closed check box.

 

Date Alias Offset

Explanation

It is possible to define a relationship between two date aliases which specifies that one will occur at a fixed interval before or after the other. This block is used to display and maintain this time relationship between two date aliases. It is also possible to ensure that no matter what date is assigned to the offset date alias, the subject date alias will not fall on specified days. This is achieved by selecting the Offset Constraints button and specifying Offset Constraints details in CALF0442.

Examples

Example 1: The last day of an examination period may always be 12 days after the first day of this period. When the two date aliases are assigned to a calendar instance and the first date is defined, the second date will be automatically calculated as 12 days later.

Example 2: A date alias for the submission of statistics to government could be defined as always occurring one month after the census date. When these two date aliases are applied to a calendar instance, and a date value for the census date defined, a date value for submission of the statistics will be automatically calculated as 1 month later. In this case the census date is called the 'Offset Date Alias' and the amount of time between the two dates is called the 'Offset Duration'.

 

To create a date alias offset for the displayed date alias, using the Maintain Date Aliases form:

  1. Enter Insert Mode.
  2. From the list of values in the Offset Date Alias field, select the date alias from which the displayed date alias will be offset.
  3. Enter the offset duration in any combination of days, weeks, months and/or years. Values may be positive or negative.
  4. Save.

Rules:

  • More than one Date Alias Offset can be defined for a Date Alias.
  • Only one offset without any calendar type restrictions can exist for a date alias.
  • To effectively use date alias offsets, date alias instances for these date aliases must be created using the Maintain Date Alias Instances (for particular calendar instances) form which is accessed via the Maintain Calendar Types form.
  • Instances of the two date aliases must occur in the same calendar instance.

To modify a date alias offset:

Rules:

To delete a date alias offset, using the Maintain Date Aliases form:

  1. Select the date alias offset record to be deleted.
  2. Delete record.
  3. Save.

Rules:

  • This function is used for the deletion of a date alias offset. If date alias instances have been created from this offset, they should be reviewed and modified if necessary using the Maintain Date Alias Instances (of a particular date alias) form.

 

Date Alias Pair

Explanation

The pairing of date aliases indicates that two dates plus every day between the two dates are represented by the relationship.

Example

Two date aliases ST-BRK and END-BRK may name the start and end dates of a mid-semester break. Pairing them defines the entire period of the break, inclusive of these two dates. When a date alias pair is created for date aliases with instances in calendars of category HOLIDAY, it effectively defines an institutional break, one of the System Date Offset Constraint Types.

 

To create a date alias pair for the displayed date alias, using the Maintain Date Aliases form:

  1. From the list of values in the Paired Date Alias field, select the Date Alias with which the displayed date alias will be paired.
    2.
  2. Save.

To modify a date alias pair, using the Maintain Date Aliases form:

Rules:

  • It is not possible to directly modify a paired date alias. To specify a pair relationship with a different date alias it is necessary to delete the existing paired date alias and create a new date alias pair.

To delete a date alias pair, using the Maintain Date Aliases form:

  1. Select the date alias pair record to be deleted.
    2.
  2. Delete record.
    3.
  3. Save.

 

Changes within this form will have the following notable effects:

  • Date Alias Offset: An occurrence date for a date alias with an offset will only be automatically generated the first time that the two related date aliases are applied to a particular calendar instance.

Last Updated 24 February, 2003.