PURPOSE: To cope with the variety of pattern in using a database and also to shorter response time by incorporating a micro computer with an associative memory provided with an associative control interface.

CONSTITUTION: The associative control interface 12 is provided, the position and size of field contributing to an associative operation are capable of setting from outside, and the interface is provided in the associative memory 67. The field that is set via this associative control interface 12 functions as an associative part contribution to the associative operation, and other fields function as the memory part of associative information. Thus, since the field contributory to the associative operation is made variable, the variety of its use pattern is enhanced in the case of forming data base in the associative memory. Also, by arranging the associative memory 67 in an address space controlled by a CPU, the time required for the retrieval of task control information is shortened.