Automated partitioning in parallel database systems

Embodiments are directed to determining optimal partition configurations for distributed database data and to implementing parallel query optimization memo data structure to improve partition configuration cost estimation efficiency. In an embodiment, a computer system accesses a portion of database data and various database queries for a given database. The computer system determines, based on the accessed database data and database queries, a partition configuration search space which includes multiple feasible partition configurations for the database data and a workload of queries expected to be executed on that data. The computer system performs a branch and bound search in the partition configuration search space to determine which data partitioning path has the lowest partitioning cost. The branch and bound search is performed according to branch and bound search policies. The computer system also outputs the partition configuration with the determined lowest partitioning cost.