Hardware-accelerated relational joins

An apparatus comprising:

• a hardware accelerator comprising a matching unit and at least one memory bank, the hardware accelerator being operative to perform a hash-join operation responsive to receiving, at a source comprising at least one database, a request to perform the hash-join operation;
• wherein the hardware accelerator is operative to perform the hash-join operation by:
• processing a first table comprising one or more rows from a memory;
• hashing at least one join column in at least one of the one or more rows of the first table to set at least one bit in at least one bit vector;
• storing in memory banks of the hardware accelerator each of the rows of the first table hashing to the same hash value;
• processing a second table comprising one or more rows from the memory;
• hashing at least one join column in at least one of the one or more rows of the second table to generate at least one hash value;
• probing the at least one bit vector using the at least one hash value;
• constructing a joined row responsive to the probing step;
• and
• outputting the joined row to the memory;
• wherein each of the rows of the first table hashing to the same hash value is stored in a separate memory bank of the hardware accelerator at a first address corresponding to the hash value;
• and
• wherein when a first memory bank of the hardware accelerator is full, subsequent rows of the first table hashing to the bit vector corresponding to the first address are stored in a second memory bank of the hardware accelerator at a second address, the second address being the next sequential address.

An apparatus comprising:

• a processor coupled to a memory and operative to:
• receive a request to perform a hash-join operation at a source comprising at least one database;
• offload the request to perform the hash-join operation to a hardware accelerator;
• and
• read a joined row from the memory;
• wherein the joined row is constructed by the hardware accelerator;
• wherein the hardware accelerator is operative to perform the hash-join operation by:
• processing a first table comprising one or more rows from the memory;
• hashing at least one join column in at least one of the one or more rows of the first table to set at least one bit in at least one bit vector;
• storing in a hardware accelerator memory each of the rows of the first table hashing to the same hash value;
• processing a second table comprising one or more rows from the memory;
• hashing at least one join column in at least one of the one or more rows of the second table to generate at least one hash value;
• probing the at least one bit vector using the at least one hash value;
• constructing a joined row responsive to the probing step;
• and
• outputting the joined row to the memory;
• wherein each of the rows of the first table hashing to the same hash value is stored in a separate memory bank of the hardware accelerator memory at a first address corresponding to the hash value;
• and
• wherein when a first memory bank of the hardware accelerator memory is full, subsequent rows of the first table hashing to the bit vector corresponding to the first address are stored in a second memory bank of the hardware accelerator at a second address, the second address being the next sequential address.