Setting valid end types

The entities allowed at each end of a link can be restricted to one or more entity types. This helps users to enter data consistently, and improves the effectiveness of searches and data analysis.

Restricting the end types that are valid for each link type forces users to enter data consistently. This can bring many advantages for users when searching and analyzing the data. For example, users can:
  • Set the end types of the links they want to browse.
  • Build queries using links with specific combinations of end type.
  • Report on links with specific combinations of end type.
  • Import and export link data with selected end types.
Some examples of links with restricted end types, in the example User Guide Database, are:
  • A Relationship link type may have a Person entity type for each end of the link.
  • An Owner link type may have Telephone and Vehicle entity types as possible End 1 types and Organization and Person entity types as possible End 2 types.
  • A Location link type may have only one entity type at one end (Address) but several possible entity types at the other end, such as Organization, Person, Vehicle.

There are two ways of reviewing and setting the entities used as end types on links:

  • For single link types, use the Link Type dialog.
  • For all link types in the current database, use the Valid End Types dialog (described below). This also enables you to find out how link end types are used in the database and to apply this usage to the database design. If you change the valid end types for a database that already contains data, you can identify which link types have invalid end types by using an Exceptions report. See below Viewing exceptions and correcting links with invalid end types.

Displaying valid end types for a link type

In the Valid End Types dialog, choose a link type from the Link Types list. The end types currently defined in the database design are shown.

The end types are sorted in alphabetical order. To sort a list with the valid end types at the top, turn on the Sort by checked check box.

Finding out how link end types are used in the database

To see a list of the available end types for the selected link type as used in the database, click Usage. To compare this with the end types defined in the database design, move the Used End Types dialog so that you can see the end type lists in the Valid End Types dialog.

You have two choices:
  • To update the design based on usage, click Replace. This replaces all the end type combinations, for the selected link, in the database design with those used in the database
  • To retain the existing design, click Close. This retains the existing database design, and you can then identify any link types with invalid end types by generating an Exceptions report (click Exceptions in the Valid End Types dialog).

Defining valid end types

In the Valid End Types dialog, the End 1 Types and End 2 Types lists show all the entity types defined in the database.
Note: Although these are called End 1 and End 2 this does not imply direction.
There are two ways of defining valid end types. You can:
  • Click Usage to display the Used End Types dialog, review how the end types are used in the database, and then click Replace to replace the end types in the database design with the end types as used in the database. You can then adjust the end type combinations further if required.
  • In the Valid End Types dialog, turn on or off the check boxes against the entity types that you want to include as valid or exclude as invalid.

When you have set the end types that you require at each end of the link type, click Apply to save the changes, or click Restore to cancel.

Restoring or applying changes

You can cancel the changes you have made to a link type by clicking Restore. You will lose any changes that you made since you last clicked Apply.

After you click Apply, you cannot restore the original end types.

Viewing exceptions and correcting links with invalid end types

Any end type combinations that are not in the database design are invalid, and may limit how users can analyze and search links. For example, in a query, users will be forced to search using the link type { Any} rather than on specific end types.

You can identify which link types in the database are used with invalid end types by producing an Exceptions report: in the Valid End Types dialog, click Exceptions.

To add the exceptions to a set, right-click on any of the branches in the tree view, for example on Exceptions or on one of the link types, and from the shortcut menu, select Add to Set. This may be useful to users who will need to correct their data.

Note: The Exceptions totals include soft deleted records, and these will be included in any sets which you create. Soft deleted records are only seen by SYSADMIN users. You may want to correct soft deleted records in order to prevent a problem from occurring where uncorrected soft deleted records are restored with invalid end types.