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<< Click to Display Table of Contents >> Referential Integrity |
  
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<< Click to Display Table of Contents >> Referential Integrity |
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An example of Referential Integrity is the Orders database, part of the Borland DBDemos, distributed via the Borland/Embarcadero development tools:
When Referential Integrity is specified for a pair of tables (e.g. Customer and Orders), a .VAL file is created with each of the tables specified in the relation (e.g. Customer.VAL and Orders.VAL).
If a table like the Parts.db table has referential relations to more than one other table, the Parts.VAL file will specify it's collection of relations.
Displaying the Referential Integrity descriptor of the Parts.db table
PdxEditor displaying the Referential Integrity descriptor for Parts.db (Borland DBDemos).
it can be seen, that relative to the Vendors table, the Parts table is the Dependent table (on Many side of a One-to-Many relation),
and to the Items side it is the Master table (on the one side of a One-to-Many relation).
The Key Field Numbers in Table is the field position in the Self table.
The Key Field Numbers in Other Table is the field position in the distant table.