Help Views

Use

You create a help view if a view with an outer join is needed as a selection method of a search help .

The selection method of a search help is either a table or a view. If you want to select data from several tables for the search help, you have to use a database view as the selection method. However, a database view always implements an inner join. If you need a view with an outer join for the data selection, you must use a help view as the selection method. In the following figure you can see the relations between a search help, a help view as the selection method and the database.

All the tables included in a help view must be linked with foreign keys. Only foreign keys that have certain attributes can be used here (see Restrictions for Maintenance and Help Views ). The first table to be inserted in the help view is called the primary tableof the help view. The tables added to this primary table with foreign keys are called secondary tables.

Caution

A help view implements an outer join, that is, all the contents of the primary table of the help view are always displayed. You must not formulate a selection condition for fields in one of the secondary tables of the help view. If records of these secondary tables cannot be read as a result of this selection condition, the system displays the contents of the corresponding fields of the secondary table with initial value.