Type of Foreign Key Fields 

Use

The type of foreign key fields describes what the foreign key fields in the foreign key table mean.

You can define the following types of foreign key field:

●      Non-key-fields/candidates:

The foreign key fields are neither primary key fields of the foreign key table nor do they uniquely identify a record of the foreign key table (key candidates). The foreign key fields do not (partially) identify the foreign key table.

●      Key fields/candidates:

The foreign key fields are either primary key fields of the foreign key table or they already uniquely identify a record of the foreign key table (key candidates). The foreign key fields identify (partially) the foreign key table.

●      Key fields of a text table:

The foreign key table is a text table for the check table. The key of the foreign key table only differs from the key of the check table in the additional language key field. This is a special case of the type Key fields/candidates.