Patent ID: 11874834
Assignee: HEWLETT PACKARD ENTERPRISE DEVELOPMENT LP
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 8:
9. An apparatus comprising:
a hardware processor; and
a memory to store instructions that, when executed by the hardware processor, cause the hardware processor to:
access a star schema-based query directed to a fact table and a plurality of dimension tables in a database, wherein the fact table has an associated primary key, and wherein the plurality of dimension tables are arranged in multiple combinations of dimension tables such that each combination of of the multiple combinations of dimension tables covers the primary key;
generate a query plan for processing the query, wherein the query plan has an associated join order and the generating of the query plan comprises:
determining costs to join subsets of dimension tables of each combination of dimension tables to the fact table;
based on the costs, select a subset of dimension tables of the subsets of dimension tables with a the lowest cost;

constrain the associated join order based on the selected subset by placing the selected subset before the fact table in the query plan; and
execute the query plan to access the database, wherein the query plan comprises joining the dimension tables in the selected subset to generate a result set before joining the result set with the fact table and then joining the remaining dimension tables in the plurality of dimension tables with the fact table.