The Foreign Key Tab is used to show Primary key to Foreign key relationships and if there is a supporting index on the foreign key.
Foreign Key Supporting Index
When a foreign key is created SQL Server does not automatically create an index. This is an end user operation.
The verification of a supporting index in is the foreign key band. The reason for this is it allows you to hide the band indexes supporting foreign key and still have visibility if there is a covering index on the foreign key.
Example below assumes
•Primary key a,b on table X
•Foreign key a,b on table Y
Column |
Index supporting Foreign Key |
Example of Supporting Index keys on table Y |
|---|---|---|
Exact Match |
Same columns, same column order |
a,b |
Overlap Match |
Same column order, more columns in the index than PK index |
a,b,c |
Covering Match |
Same columns different order |
b,a |
FK Has Index |
If any of the above conditions are met then there is a supporting index |
The view is a banded view with the following bands
1.Foreign Key
2.Indexes Supporting Foreign Key
3.Primary Key
The foreign key band is pinned to the left allowing this to be visible while scrolling the grid
