Third-Generation Database System manifesto The committee for advanced Database Management System (DBMS) Function

Question: What is the path we must follow to arrive at the next generation of DBMS?

Current state description from authors (1990) Current state description from authors (1990) Mainly 2 nd generation DBMS Mainly 2 nd generation DBMS Agreement in industry that the current DBMS need extended capabilities. Agreement in industry that the current DBMS need extended capabilities. There is a need for getting the common understanding of where we are going down on the paper. There is a need for getting the common understanding of where we are going down on the paper. A counterweight to the spreading object- oriented enthusiasm is needed. A counterweight to the spreading object- oriented enthusiasm is needed.

What is needed: A gradual transition from 2nd generation DBMS to a 3rd generation DBMS

First Tenet Besides traditional database management services, third generation DBMSs will provide support for richer object structures and rules

Second Tenet Third generation DBMSs must subsume second generation DBMS.

Third Tenet Third generation DBMSs must be open to other subsystems.

(1. Tenet) Object and Rule Management A rich type system is needed (including extensions to query language). A rich type system is needed (including extensions to query language). (Multiple- ) Inheritance is a good idea. (Multiple- ) Inheritance is a good idea. Functions, including database procedures and methods, and encapsulation are a good idea. Functions, including database procedures and methods, and encapsulation are a good idea. Unique IDs should only be reassigned if human defined primary key is not available. Unique IDs should only be reassigned if human defined primary key is not available. Rules are important. Rules are important.

(2. Tenet) Increasing DBMS Function Programmatic access should be through a non- procedural high-level access language (minimal navigation). Programmatic access should be through a non- procedural high-level access language (minimal navigation). Collections should be definable both through member enumeration and through queries (extensionally vs. intentionally). Collections should be definable both through member enumeration and through queries (extensionally vs. intentionally). Updatable views are essential. Updatable views are essential. Performance indicators must not appear in data models. Performance indicators must not appear in data models.

(3. Tenet) Need for an open system. DBMSs must be accessible through multiple higher level languages. DBMSs must be accessible through multiple higher level languages. Persistent objects is a good idea. Persistent objects is a good idea. SQL will prevail. SQL will prevail. Queries and result set should be the lowest level of communication. Queries and result set should be the lowest level of communication.

Needed improvements in current DBMS to become 3 rd generation DBMS Improvements in relational databases systems: inheritance and additional type constructors. Improvements in relational databases systems: inheritance and additional type constructors. Improvements in object-oriented database systems: query language, query optimizers, views and SQL support. Improvements in object-oriented database systems: query language, query optimizers, views and SQL support. Both database systems need support for persistent programming languages. Both database systems need support for persistent programming languages.

Conclusion Object-oriented databases is not the solution to the challenges found in using 2 nd generation DBMSs. Object-oriented databases is not the solution to the challenges found in using 2 nd generation DBMSs. The existing experience and expertise built into the existing relational databases should be used as much as possible. The existing experience and expertise built into the existing relational databases should be used as much as possible. Development based on the current 2 nd generation DBMS is more sensible than new development from scratch. Development based on the current 2 nd generation DBMS is more sensible than new development from scratch.