Subject
Computer Science
Topic
Computer Hardware
In a database, what is a 'primary key'?
In a database, what is a 'primary key'?
a)
The first column in every table.b)
A field in a table that uniquely identifies each record in that table.c)
A key used to encrypt the database.d)
A field that links to a primary key in another table.Explanation
The primary key is a crucial concept in relational databases. It must contain unique values for each row of data and cannot contain null values. It ensures data integrity and is used to create relationships with other tables via foreign keys.Related questions
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