2. A method of representing a database query expression for use during execution of the query expression by a computer, wherein the database query expression includes a plurality of predicates related to one another by at least one logical relation, the method comprising: generating a plurality of operands from the database query expression, wherein each operand in the plurality of operands is representative of a predicate in the plurality of predicates; mapping each operand among the plurality of operands into an operand map; and generating a hierarchical data structure based upon the generated plurality of operands, wherein the data structure includes a plurality of nodes, wherein each node includes an operand identifier that identifies at least one operand from the plurality of operands based upon the operand map, wherein each node defines a first logical relation between those predicates in the database query expression that are represented by operands identified by the operand identifier for such node, and wherein the plurality of nodes are arranged relative to one another in the data structure within multiple hierarchical levels to define at least a second logical relation among predicates in the database query expression.
2. A method of representing a database query expression for use during execution of the query expression by a computer, wherein the database query expression includes a plurality of predicates related to one another by at least one logical relation, the method comprising: generating a plurality of operands from the database query expression, wherein each operand in the plurality of operands is representative of a predicate in the plurality of predicates; mapping each operand among the plurality of operands into an operand map; and generating a hierarchical data structure based upon the generated plurality of operands, wherein the data structure includes a plurality of nodes, wherein each node includes an operand identifier that identifies at least one operand from the plurality of operands based upon the operand map, wherein each node defines a first logical relation between those predicates in the database query expression that are represented by operands identified by the operand identifier for such node, and wherein the plurality of nodes are arranged relative to one another in the data structure within multiple hierarchical levels to define at least a second logical relation among predicates in the database query expression. 4. The method of claim 2 , wherein the data structure comprises a tree, the tree comprising at least one level.