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SQL Server

What is the key ?

Asked by Ito Yamaguchi Dec 28, 2019 1.3K views 1 answer
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Preetam Shetty JanBask Expert Latest answer

Answered on Nov 10, 2019

  1. A key is a value that is used to identify a record uniquely in a table .
  2. Keys can be defined on single or multiple columns depending on the requirement.
  3. Columns that are used to define a key is known as key column
  4. Similarly, columns that are not used to define a key are called non-key columns.


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