Maintains database by entering new and updated customer and account information. Prepares source data for computer entry by compiling and sorting information. Establishes entry priorities. Processes customer and account source documents by reviewing data for deficiencies. Enters customer and account data by inputting alphabetic and numeric information on keyboard or optical scanner according to screen format. Verifies entered customer and account data by reviewing, correcting, deleting, or reentering data. Purges files to eliminate duplication of data.