documents/megalog/database-sec.tex

6 % in compliance with the License.  You may obtain a copy of the License
57 has a one-to-one correspondence with a predicate
61 by extracting single tuples from a relation with {\eclipse}'s `tuple-at-a-time' operations.
74 is comparable with both Prolog compilers (which only access clauses in main memory),
76 with the functionality of both without losing the performance of either.
78 \eclipse provides two versions of its database, one with the deductive
109 A database is created with the predicate {\bf createdb/1}. \index{createdb/1}
125 be created within `/usr/applic/' with the name `bank\_data'.
144 attributes. This information is entered in the database with the
201 The two examples produce relations with the same attributes, but
248 tree. This achieves good performance even with varying and unpredictable
319 relation by its synonym is when it is being joined with itself
361 relation along with the above information the {\bf printrel/1}
394 with relational algebra.
464 Any operator may compare either two attributes or an attribute with
485 with `F'. Note that the wild character `\verb-*-' may only occur as last
549 with each other or with constants using any comparison operator.
583 with each other or with constants using any comparison operator.
612 The operations presented so far create relations with all the attributes
636 This creates the relation {\bf man\_grade1/2}, with a schema that satisfies
649 Adding tuples to a relation is performed with the \verb-<++/2- predicate,
736 So in the example all the tuples with
781 In the example below there is an employee relation with three attributes.
783 relation with two aggregating attributes is setup.
827 of values into a relation with an attribute of type term:
923 the same operations. Below we illustrate this duality with an example
938 On the other hand the tuple access allows an easy interference with
953 Then a tuple can be retrieved from the relation {\bf p/2} with the