PURPOSE: To sort the concentrated data into those data that are handled in a patch program system by setting a terminal name and a data file name to a transmission control file and a concentration control data base respectively.

CONSTITUTION: A terminal 1 and a host computer 8 control the name of the terminal 1 and the name of data files 4, 5 and 6 by means of a transmission control file 7 and a concentration control data base 9 respectively. When a transmission program 3 is started in a concentration processing state, a file to be transmitted is decided based on the contents of the file 7 and the files 4 - 6 are transmitted just by a single processing operation. When the data are received from the terminal 1, a concentration program 15 is started to decide a terminal name and a data file name transmitted from the program 3 and writes a terminal name 14 and a data group 10 into a data base 9. In an extraction processing state, an extraction program 16 is started to select the data stored in the group 10 after distributing them for each data file 17. In such a constitution, the concentrated data can be sorted into the data that are handled in a patch program system.