Inpixon
Joining large database tables

Abstract:

Techniques to process a query and perform a join of tables that are distributed across nodes of a network. The join can be performed by analyzing a Where clause. An active flag structure can have flag values that identify table entries satisfying criteria of the Where clause. Keys of surviving entries of a first table can be used to generate a request for a second table to be joined. The request can be for second flags for the second table when the Where clause has criteria for the second table. A response can be used to update the first flags to change a first flag to False. After updating, data can be retrieved for first flags that are True. Requests can use identifiers associated with the first table that identify a location for sending the request, e.g., using RDMA or MPI.