Ted Codd’s paper which established the equivalence in expressive power between relational calculus and relational algebra.
Databases are an example of program synthesis, while a query optimizer might use heuristic search.
Selinger (et al.) paper on the cost-based optimizer.
David J. DeWitt and Michael Stonebraker argued that MapReduce was a step backwards for the database community.
Stonebraker and Pavlo’s analysis of 20 years of data models.
Sonebraker and Hellerstein’s summary of 35 years of data models.
David J. DeWitt and Michael Stonebraker’s views on MapReduce.
Andy Pavlo’s lecture on his paper “What Goes Around Comes Around… And Around…”.
A successful write by a database does not necessarily mean durability on disk.