Abstract: A method executed by a computer, the method includes receiving first information that indicates a plurality of functions provided in a first computing system when the plurality of functions are migrated from the first computing system to a second computing system, specifying a first linkage state of the plurality of functions in the first computing system, specifying a second linkage state of the plurality of functions in the second computing system, specifying a first performance determined based on the first linkage state, the first performance being performance of the plurality of functions in the first computing system, specifying a second performance determined based on the second linkage state, the second performance being performance of the plurality of functions in the second computing system, determining a first difference between the first performance and the second performance, and outputting the first difference.

Abstract: A database control method includes generating a second database in which recorded contents of a first database are copied, when detecting an update program for updating a first control program configured to control the first database set as a transmission destination of a request for processing transmitted by a terminal apparatus; generating a second control program by updating the first control program using the update program; setting the transmission destination to both the first database and the second database; executing the processing on the first database using the first control program; executing the processing on the second database using the second control program; setting the transmission destination to the second database when a first result of the processing on the first database and a second result of the processing on the second database match; and executing processing on the second database using the second control program when receiving the request.