Systems, Methods, And Devices For Managing Data Skew In A Join Operation

Non-transitory computer readable storage media storing instructions that, when executed by one or more processors, cause the one or more processors to:

• compute a hash value for a join operation;
• detect data skew on a probe side of the join operation at a runtime of the join operation using a lightweight sketch data structure;
• identify a frequent probe-side join key on the probe side of the join operation during a probe phase of the join operation;
• identify a frequent build-side row having a build-side join key corresponding with the frequent probe-side join key;
• and
• asynchronously distribute the frequent build-side row to one or more remote servers.

A system for managing data skew, the system comprising:

• a means for computing a hash value for a join operation;
• a means for detecting data skew on a probe side of the join operation at a runtime of the join operation using a lightweight sketch data structure;
• a means for identifying a frequent probe-side join key on the probe side of the join operation during a probe phase of the join operation;
• a means for identifying a frequent build-side row having a build-side join key corresponding with the frequent probe-side join key;
• and
• a means for asynchronously distributing the frequent build-side row to one or more remote servers.