Patent ID: 7536379
Filing Date: 2009-05-19
Classification: G06F,Y10S

Abstract:
1. A computer-implemented method for processing a multiple table query that utilizes a join operation having a join sequence in which results of the query applied to each of the tables in the multiple tables are joined in a sequential order in a database system, the method comprising: determining one or more tables in the multiple table query that require materialization; for each of the one or more tables, deriving a join predicate on a join column of the table; for each table having a derived join predicate, identifying at least one other table, whose results are to be joined prior, in the join sequence, to joining results of the query on the table, having a same join predicate; responsive to identifying the at least one other table having the same join predicate, applying the derived join predicate to the at least one other table in the join sequence to reduce an amount of rows that need to be joined between the tables in the multiple table query during processing of the join sequence; and storing a result of applying the derived join predicate.