Basic HTML version of Foils prepared 7 October 97

Foil 65 Database Design - III

From Overview of JDBC and its use with Microsoft Access ARL Database Tutorial -- February 98. by Nancy McCracken(Sangetta Aggarwal, Udayan Parvate, Tom Pulikal)
Many-to-Many - For each row in the first table, there can be many rows in the second table, and for each row in the second table, there can be many rows in the first table.
The relational model specifies two Integrity rules:
  • Entity integrity rule - Primary keys cannot contain null (missing) data.
  • Referential integrity rule - The database must not contain any unmatched foreign key values.

© on Mon Oct 13 1997