Learn how to add and remove Primary Keys from an Access database table. The primary key's purpose is to promptly associate data from multiple tables and combine that data.

Some database designers may feel that it’s OK to arbitrarily assign all dimensional foreign keys as part of a fact’s primary key even when one or more do not actually contribute to the fact table’s ...

The column (field) in a relational database that uniquely identifies the row in the table. For example, account number is often a primary key. A "composite primary key" or "super key" is made up ...

Under far too many circumstances, those responsible for modeling data are ignoring the above perspective on primary keys and are simply defining surrogate keys for everything in their data model. One ...

Duplicate and Ignore on MySQL Inserts. MySQL table primary keys and unique indexes prevent multiple rows with the same index from being added to the table. If you try to insert a duplicate row ...

The primary keys provide administrator level access to Cosmos DB instances with full read/write/delete permissions. The database service also requires users to have secondary keys as well to make ...