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Next: The Condition Box Up: Query-by-Example (QBE) Previous: Simple Queries

Queries on Several Relations

  1. Queries on several relations require several skeleton tables.
  2. To find the name and city of all customers having a loan at the SFU branch:



  3. Find the name of all customers having an account at the SFU branch, but no loan from that branch.

    Queries involving negation can be expressed by putting a tex2html_wrap_inline460 sign under the relation name beside an example row:



  4. To find all customers who have accounts at two different branches:


Osmar Zaiane
Tue Jun 9 14:17:04 PDT 1998