He invented Alpha as part of his relational theorem, although it was never implemented. QUEL, of the Ingres/Postgres lineage, was heavily influenced by the desi

He invented Alpha as part of his relational theorem, although it was never implemented. QUEL, of the Ingres/Postgres lineage, was heavily influenced by the design of Alpha and is the closest thing we have to what he envisioned. SQL comes from Boyce and Chamberlain.