Access Path Selection in a Relational Database Management System (1979)
by Patricia Griffiths Selinger, Morton Astrahan, Donald Chamberlin, Raymond Lorie, Thomas Price Ā· ACM SIGMOD / UC Berkeley course mirror
The System R paper that introduced cost-based query optimization. Defines selectivity factors, access path costing and dynamic-programming join ordering ā the model nearly every relational optimizer still uses, which is what makes modern EXPLAIN output legible.
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