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Primary keys

Last modified: 11 October 2024

A primary key contains unique values and identifies each row in a table.

For some databases, the primary key cannot contain NULL values. A table can have only one primary key, and this primary key can consist of single or multiple columns. When a primary key consists of multiple columns, the data from these columns is used to determine whether a row is unique.

Primary keys ( Primary Key) can be found in the Database tool window.

Primary keys in Database