Abstract: A method, system and computer program product are disclosed for morphing an object from one class to another in an object oriented computing environment implemented by a relational database. Object morphing functionality is provided by first defining object classes, class attributes, class relationships, objects, object attributes and object relationships as tables of data in the relational database. In response to user input representing a request to reassign one of the objects from one class to another, a class identifier corresponding to the object in the database tables is changed. The object's edge relationships with other objects are then checked for continued validity and an error message is generated if any such edge relationships are no longer valid. If the object's edge relationships are valid, the attributes of the object are modified to reflect the new class assignment.

Abstract: Certain types of modeling problems solvable using object oriented computer programming languages can be solved using standard structure query programming languages (SQL). By appropriately tabulating relationships of these problems, the tables can be operated on using predetermined SQL procedures that can use well-known object oriented computer programming language concepts.

Abstract: Any existing transitive closure in a database can be found using a method based on standard 4th Generation Structured Query Language (SQL) without non-standard extensions to perform recursion analysis. Once a transitive closure table is compiled, SQL and the transitive closure table can be used to calculate critical path lengths, sums, averages, or other values, through a directed acyclical graph. Since this method uses instructions that are entirely within standard 4GL SQL, it can be used over multiple platforms as long as the platforms are 4GL SQL compliant.

Abstract: Fourth generation structured query languages can be used to aggregate scalars associated with the nodes of a directed acyclic graph. Node tables, edge tables, and a transitive closure table can be used to perform these aggregate operations. The invention provides a declarative methodolgy for calculating values associated with the node of a directed acyclic graph.

Abstract: Any existing transitive closure in a database can be found using a method based on standard 4th Generation Structured Query Language (SQL) without non-standard extensions to perform recursion analysis. There are no requirements to stay within a preset number of levels in the database to prevent breakdown as in previous known methods. The method represents each database as a graph and builds path and edge tables which are updated as data, that is verticies and edges, are added or deleted. Since this method uses instructions that are entirely within standard 4GL SQL, it can be used over multiple platforms as long as the platforms are 4GL SQL compliant.