| **Navigation:**  [[glossary index.htm|Glossary Index]] >====== database integrity ============ Under the relational model, database integrity consists of two general rules: ============  ============ 1. Each database file or table must have a primary key serving as a unique identifier for all records. ============  ============ 2. When a table has a foreign key matching the primary key of another table, each value in the foreign key must either equal a value in the primary key of the other table, or be null. ====== | [[database driver.htm|{{btn_prev_n.gif|Previous page}}]][[glossary index.htm|{{btn_home_n.gif|Return to chapter overview}}]][[dbase format.htm|{{btn_next_n.gif|Next page}}]] |
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