16.20 - Referential Integrity - Teradata Database - Teradata Vantage NewSQL Engine

Teradata Vantageâ„¢ SQL Fundamentals

Product
Teradata Database
Teradata Vantage NewSQL Engine
Release Number
16.20
Published
March 2019
Language
English (United States)
Last Update
2019-05-02
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Referential integrity (RI) is defined as all the following notions.

  • The concept of relationships between tables, based on the definition of a primary key (or UNIQUE alternate key) and a foreign key.
  • A mechanism that provides for specification of columns within a referencing table that are foreign keys for columns in some other referenced table.

    Referenced columns must be defined as Primary key columns or Unique columns.

  • A reliable mechanism for preventing accidental database corruption when performing inserts, updates, and deletes.

Referential integrity requires that a row having a value that is not null for a referencing column cannot exist in a table if an equal value does not exist in a referenced column.