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We'll look at examples from the text.
- QBE has ``two-dimensional'' syntax.
- Queries are expressed by example.
- Close correspondence with domain relational calculus
- Queries are expressed using skeleton tables.
- User selects the skeletons needed.
- User fills in skeletons with example rows.
- An example row consists of constants and example elements which
are really domain variables.
- Domain variables are preceded by an underscore character.
- Constants appear without any qualification.
Tue Jun 9 14:17:04 PDT 1998