Query processing in a polystore

A computer-implemented method, comprising:

• generating, based at least on an analysis plan, a logical plan, the analysis plan specifying one or more operations performed on at least a portion of data stored in a polystore that includes a first database management system and a second database management system, the logical plan including a sequence of logical operators corresponding to the one or more operators specified by the analysis plan, the generating of the logical plan includes rewriting the sequence of logical operators by at least reordering, replacing, and/or combining one or more logical operators in the sequence of logical operators;
• generating, based at least on the logical plan, a plurality of candidate physical plans;
• generating a cross-model index for a first data stored in the first database management system having a first data model and a second data stored in the second database management system having a second data model;
• and
• executing, based at least on the cross-model index and a physical plan selected from the plurality of candidate physical plans, the analysis plan.

A non-transitory computer readable medium storing instructions, which when executed by at least one data processor, result in operations comprising:

• generating, based at least on an analysis plan, a logical plan, the analysis plan specifying one or more operations performed on at least a portion of data stored in a polystore that includes a first database management system and a second database management system, the logical plan including a sequence of logical operators corresponding to the one or more operators specified by the analysis plan, the generating of the logical plan includes rewriting the sequence of logical operators by at least reordering, replacing, and/or combining one or more logical operators in the sequence of logical operators;
• generating, based at least on the logical plan, a plurality of candidate physical plans;
• generating a cross-model index for a first data stored in the first database management system having a first data model and a second data stored in the second database management system having a second data model;
• and
• executing, based at least on the cross-model index and a physical plan selected from the plurality of candidate physical plans, the analysis plan.