Abstract: A cost based optimizer and a cost estimation method and device. The method includes: in response to deciding that acquired statistical information is incomplete, determining a corresponding cost estimation manner according to an operation type of an operation tree relying on the statistical information (S11); determining a cost estimate of the corresponding operation type based on the cost estimation manner (S12); and determining an accumulative cost estimate of the operation tree according to the cost estimate corresponding to the operation type relying on the statistical information and a cost estimate corresponding to an operation type not relying on the statistical information (S13). Therefore, cost estimation may be performed for a temporary table and a subquery created in a running process, and is not limited by a data scale in a scenario of massive data.

Abstract: A cost based optimizer and a cost estimation method and device. The method includes: in response to deciding that acquired statistical information is incomplete, determining a corresponding cost estimation manner according to an operation type of an operation tree relying on the statistical information (S11); determining a cost estimate of the corresponding operation type based on the cost estimation manner (S12); and determining an accumulative cost estimate of the operation tree according to the cost estimate corresponding to the operation type relying on the statistical information and a cost estimate corresponding to an operation type not relying on the statistical information (S13). Therefore, cost estimation may be performed for a temporary table and a subquery created in a running process, and is not limited by a data scale in a scenario of massive data.

Abstract: A method, apparatus and computer program, each for optimizing execution of a computer program is disclosed in which a topology-based control flow analysis of basic blocks of the computer program is performed and a data flow analysis of the instructions within the basic blocks is performed to determine if each instruction of said computer program is uniform or non-uniform (variant or invariant). Subsequently, when the computer program is executed, storage of a copy of a variable dependent on a uniform instruction is suppressed.

Abstract: A computer-implemented method and system for improved data flow analysis and optimization are disclosed. The method and system generates data flow analysis information from vectorized processing components, the data flow analysis information including an input information set and an output information set, generates hole information from the vectorized processing components, selects needed holes based on the input information set, the output information set, and the hole information, and modifies a portion of the data flow analysis 10 information by retaining needed holes and removing holes not identified as needed holes from the vectorized processing components.

Abstract: A computer-implemented method and system for improved data flow analysis and optimization are disclosed. The method and system generates data flow analysis information from vectorized processing components, the data flow analysis information including an input information set and an output information set, generates hole information from the vectorized processing components, selects needed holes based on the input information set, the output information set, and the hole information, and modifies a portion of the data flow analysis 10 information by retaining needed holes and removing holes not identified as needed holes from the vectorized processing components.