Patent ID: 9177026
Filing Date: 2015-11-03
Classification: G06F

Abstract:
1. A method to join records from a set of at least three tables in a database according to a set of join conditions on a set S of join attributes, the method comprising: arranging the join attributes S into an ordered sequence S initializing a scope C to empty; identifying tables in the set of tables that include a join attribute A that is first in the ordered sequence S creating a new sequence S′ of join attributes that omits the join attribute A from S iterating through each of the identified tables in join attribute A order, the iterating based on a tree index structure for each of the identified tables where the index key includes all join attributes in the identified table in S for each matched value v of the join attribute located during the iterating, creating a new scope C determining whether S′ is empty; based on determining that S′ is empty, outputting a tuple corresponding to the scope C based on determining that S′ is not empty, setting S