Patent ID: 8375031
Filing Date: 2013-02-12
Classification: G06F,H04L

Abstract:
1. A method, comprising: defining an operator stack in a memory, the operator stack adapted to store binary logical operators; defining a value stack in the memory, the value stack adapted to contain pointers to nodes of a filter expression tree; parsing the filter expression on an element-by-element basis, elements of the filter expression comprising operators and values, wherein for each next element in the filter expression: removing a completed binary tree from the value stack; defining stacks in a memory corresponding to a left sub-tree stack (L-stack), a right sub-tree stack (R-stack), a result of left sub-tree stack (RL-stack), and a result of right sub-tree stack (RR-stack); performing a post-order traversal of the nodes of the completed binary tree in which each node of completed binary tree is visited, wherein during the post-order traversal: processing a root node of the binary tree; removing the disjunctive normal form of the filter expression from the RL-stack or the RR-stack corresponding to the root node; and identifying overlapping keys from the disjunctive normal form of the filter expression.