History of PC DBMS: Which product first implemented true relational algebra on a personal computer DBMS?

Introduction / Context:
Relational algebra underpins the relational model. Early personal computer (PC) DBMS products varied in how faithfully they implemented relational principles.

Given Data / Assumptions:

• We focus on PC DBMS history, not mainframe/enterprise systems.

Concept / Approach:
Among PC databases, R:base is recognized for implementing true relational algebra early in the PC space, in contrast to file-oriented products like dBase-II.

Step-by-Step Reasoning:

Verification / Alternative check:
Historical references and industry retrospectives place R:base as an early adopter of relational theory on PCs.

Why Other Options Are Wrong:

• IDMS → network database (mainframe heritage), not a PC pioneer in relational algebra.
• Oracle → enterprise RDBMS, not the first on PCs in this context.
• dBase-II → xBase family; largely file-based, not fully relational algebra.

Common Pitfalls:
Assuming enterprise leaders (e.g., Oracle) were first on PCs or conflating “SQL support” with strict relational algebra implementation in early PC products.

Final Answer:
R:base