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Guidlines for primary keys and foreign keys

Posted by Manish Tewatia in Blogs | Oracle on Apr 13, 2011

This is about the guidlines for primary keys and foreign keys in oracle.

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The guidelines you have to follow when you work with primary keys and foreign keys in oracle are:-

You cannot use duplicate values in a primary key.
Primary keys generally cannot be changed.
Foreign keys are based on data values and are purely logical, not physical, pointers.
A foreign key value must match an existing primary key value or unique key value, or else be null.
A foreign key must reference either a primary key or unique key column.

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