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"unique key" is a pointless tautology - keys are unique by definition. To be absolutely clear I have substituted "candidate key" instead.
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nvogel
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Keys are for identification and data integrity. A key defines how tuples (rows) in a table can be uniquely identified. The integrity of keys is assured because the DBMS prevents users from entering duplicate information into the table. Database users can therefore rely on the keys to identify in the real world the things recorded in the database.

A "primary" key is fundamentally no different from any other candidate key in the same table. It's just a convention used to designate one key per table as significant in some way. Usually it is the "preferred" or "most important" key of a table and the one used in foreign key references.

Keys are for identification and data integrity. A key defines how tuples (rows) in a table can be uniquely identified. The integrity of keys is assured because the DBMS prevents users from entering duplicate information into the table. Database users can therefore rely on the keys to identify in the real world the things recorded in the database.

A "primary" key is fundamentally no different from any other key in the same table. It's just a convention used to designate one key per table as significant in some way. Usually it is the "preferred" or "most important" key of a table and the one used in foreign key references.

Keys are for identification and data integrity. A key defines how tuples (rows) in a table can be uniquely identified. The integrity of keys is assured because the DBMS prevents users from entering duplicate information into the table. Database users can therefore rely on the keys to identify in the real world the things recorded in the database.

A "primary" key is fundamentally no different from any other candidate key in the same table. It's just a convention used to designate one key per table as significant in some way. Usually it is the "preferred" or "most important" key of a table and the one used in foreign key references.

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nvogel
  • 3.8k
  • 20
  • 25

Keys are for identification and data integrity. A key defines how tuples (rows) in a table can be uniquely identified. The integrity of keys is assured because the DBMS prevents users from entering duplicate information into the table. Database users can therefore rely on the keys to identify in the real world the things recorded in the database.

A "primary" key is fundamentally no different from any other unique key in the same table. It's just a convention used to designate one key per table as significant in some way. Usually it is the "preferred" or "most important" key of a table and the one used in foreign key references.

Keys are for identification and data integrity. A key defines how tuples (rows) in a table can be uniquely identified. The integrity of keys is assured because the DBMS prevents users from entering duplicate information into the table. Database users can therefore rely on the keys to identify in the real world the things recorded in the database.

A "primary" key is fundamentally no different from any other unique key in the same table. It's just a convention used to designate one key per table as significant in some way. Usually it is the "preferred" or "most important" key of a table and the one used in foreign key references.

Keys are for identification and data integrity. A key defines how tuples (rows) in a table can be uniquely identified. The integrity of keys is assured because the DBMS prevents users from entering duplicate information into the table. Database users can therefore rely on the keys to identify in the real world the things recorded in the database.

A "primary" key is fundamentally no different from any other key in the same table. It's just a convention used to designate one key per table as significant in some way. Usually it is the "preferred" or "most important" key of a table and the one used in foreign key references.

Keys are for identification and data integrity. A key defines how tuples (rows) in a table can be uniquely identified. The integrity of keys is assured because the DBMS prevents users from entering duplicate information into the table. Database users can therefore rely on the keys to identify in the real world the things recorded in the database.

A "primary" key is fundamentally no different from any other unique key in the same table. It's just a convention used to designate one key per table as significant in some way. Usually it is the "preferred" or "most important" key of a table and the one used in foreign key references.

Keys are for identification and data integrity. A key defines how tuples (rows) in a table can be uniquely identified. The integrity of keys is assured because the DBMS prevents users from entering duplicate information into the table. Database users can therefore rely on the keys to identify in the real world the things recorded in the database.

A "primary" key is fundamentally no different from any other key in the same table. It's just a convention used to designate one key per table as significant in some way. Usually it is the "preferred" or "most important" key of a table and the one used in foreign key references.

Keys are for identification and data integrity. A key defines how tuples (rows) in a table can be uniquely identified. The integrity of keys is assured because the DBMS prevents users from entering duplicate information into the table. Database users can therefore rely on the keys to identify in the real world the things recorded in the database.

A "primary" key is fundamentally no different from any other unique key in the same table. It's just a convention used to designate one key per table as significant in some way. Usually it is the "preferred" or "most important" key of a table and the one used in foreign key references.

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nvogel
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