BUSINESS ADMINISTRATION
COMPUTER APPLICATION IN BUSINESS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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candidate, primary
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primary, foreign
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candidate, foreign
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foreign, alternate
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Detailed explanation-1: -Primary key is the Candidate key selected by the database administrator to uniquely identify tuples in a table. Out of all the Candidate keys that can be possible for a table, only one key will be used to retrieve unique tuples from the table. This Candidate key is called the Primary Key.
Detailed explanation-2: -No. The primary key uniquely identifies a record or row in the table and it follows one key per table approach. The candidate key also uniquely identifies a record or row in the table but it can have one key per table or many keys per table. The primary key is a minimal super key.
Detailed explanation-3: -In a relational database, a candidate key can be a single column or combination of more than one column that could be used as a primary key. A “minimal super key” is called a candidate key. The candidate key can have a NULL value, unlike a primary key. A candidate key may or may not be a primary key.
Detailed explanation-4: -Both Primary Key and Candidate Key are the attributes that are used to access tuples from a table. These(Primary key and Candidate key) are also can be used to create a relationship between two tables.