Abstract: A method, apparatus, and article of manufacture for improving the performance of evaluating predicates with non-matching operands by aggressively casting the input value to the data type of the target column before the data of the target column is accessed.

Abstract: A method, apparatus, and article of manufacture for improving the performance of evaluating predicates with non-matching operands by aggressively casting the input value to the data type of the target column before the data of the target column is accessed.

Abstract: A technique for optimizing execution of a query that accesses data stored on a data store connected to a computer. Query predicates involving different data types are identified. A second query predicate is generated which includes matching data types, and if necessary, converted operators. The second query predicate with the matching data types and/or converted operators is executed to obtain a subset of records using an index manager or data manager. The subset of records is converted to the data types of the remaining query predicates. The first query predicate is applied against the subset of records to obtain a result, and the remaining query predicates of the original query are applied to the result of the first query predicate and any other additional converted query predicates to obtain a final result.

Abstract: A technique for optimizing execution of a query that accesses data stored on a data store connected to a computer. Query predicates involving different data types are identified. A second query predicate is generated which includes matching data types, and if necessary, converted operators. The second query predicate with the matching data types and/or converted operators is executed to obtain a subset of records using an index manager or data manager. The subset of records is converted to the data types of the remaining query predicates. The first query predicate is applied against the subset of records to obtain a result, and the remaining query predicates of the original query are applied to the result of the first query predicate and any other additional converted query predicates to obtain a final result.

Abstract: A method, apparatus and article of manufacture for computer implemented method of efficiently executing built-in functions is defined. Function modules are defined to process a single data type class and to process as many functions as possible before returning to the caller. Functions related to a query are each assigned a key, a type of code, to indicate the data type class to which the function belongs. The functions are then ordered so that a particular module scope can be held as long as possible. Further, data fields, another type of code containing optimization information, can be added to the functions to further enable the holding of module scope. Finally, the functions are executed at runtime. During execution, the database system looks ahead at upcoming functions in an attempt anticipate the next course of action by examining the keys and data fields. Various additional optimization techniques can then be used to enhance runtime performance.