Adaptive selection of a distribution method during execution of parallel join operations

A computer system for adaptive selection of distribution methods responsive to measurements taken during execution of parallel join operations over two relations, comprising:

• a computer processor to execute a set of program code instructions;
• and
• a memory to hold the program code instructions, in which the program code instructions comprises program code to perform,
• estimating, during a compile phase, a system cost of performing the parallel join operations over the two relations;
• selecting, during the compile phase, a first distribution method to perform the parallel join operations;
• communicating first distribution method instructions to two or more execution units, the first distribution method instructions according to the selected first distribution method;
• collecting, from at least one of the two or more execution units, at least some measurements pertaining to performing a first portion of the parallel join operations using the selected first distribution method;
• selecting, based at least in part on the measurements, a second distribution method;
• and
• communicating second distribution method instructions to the two or more execution units.

A computer program product embodied in a non-transitory computer readable medium, the computer readable medium having stored thereon a sequence of instructions which, when executed by a processor causes the processor to execute a process to implement adaptive selection of distribution methods responsive to measurements taken during execution of parallel join operations over two relations, the process comprising:

• estimating, during a compile phase, a system cost of performing the parallel join operations over the two relations;
• selecting, during the compile phase, a first distribution method to perform the parallel join operations;
• communicating first distribution method instructions to two or more execution units, the first distribution method instructions according to the selected first distribution method;
• collecting, from at least one of the two or more execution units, at least some measurements pertaining to performing a first portion of the parallel join operations using the selected first distribution method;
• selecting, based at least in part on the measurements, a second distribution method;
• and
• communicating second distribution method instructions to the two or more execution units.