In order to improve the efficiency of execution of a program by prefetching data necessary to execute the program, a system is provided that causes a computer to execute a recursive query prior to a program being subjected to prefetching. This system detects from iterative processing in the program a query to generate a resultant table by selecting a record that satisfies a selection condition from a target table. The system generates an initial query to generate an initial table that includes values of variables that are set prior to starting the iterative processing in the program. Furthermore, the system generates a recursive query to generate the next intermediate table that is referred to in the next and later cycles of the iterative processing, in the recursive query corresponding to each cycle of the iterative processing that is sequentially performed, from an intermediate table that includes resultant tables generated by a target query in the preceding cycles of the iterative processing and the target table. Furthermore, the system generates a final query to generate a final table from the intermediate table sequentially generated by the recursive query.