A formal basis for extending SQL to object-oriented databases
نویسنده
چکیده
A formal basis for extending SQL in a natural way to complex ob ject databases is laid NSQL a language equivalent to the standard algebra for nested relational databases is obtained It is also shown that when allowing subqueries in the from clause the facility of sub queries in where clauses becomes redundant with regard to expressive power
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عنوان ژورنال:
- Bulletin of the EATCS
دوره 40 شماره
صفحات -
تاریخ انتشار 1990