PURPOSE: To perform data insertion/deletion to sequential data such as genes without influencing the following data by providing a function meaning branching and returning points in a code string to be inserted.

CONSTITUTION: A function block 201 is the function block for indicating data branching and the function block 202 indicates the conditions of branching. For instance, when no insertion block is present in front, the next data are acquired without branching. Also, when an instruction for not reading the insertion data is issued in a request at the time of read, the data are read without branching when the conditions coincident with the instruction code are entered. Also, the function block 203 is the function block for indicating the location of the insertion data and the function block 204 indicates the example of the insertion of a dummy block considering future expansion. The function block 205 indicates that the function block is to be comleted and also indicates the code string for instructing branching to the following data and the function block 206 indicates the branching address.