A Data processing procedure normally consists of a number of basic processing operations performed in some order (not necessarily the order of their description below). The means of performing the processing operation vary according to whether manual, electromechanical, or electronic methods are used. Many business find that the best solution to their processing requirements is to use a combination of methods; e.g., manual may be used for small-volume jobs while computers may be used for large-volume tasks.
1. Recording. Recording refers to the transfer of data onto some form of documents. It relates to the documentation of intermediate figures and facts and resulting from calculations. For example, in computing gross pay, the numbers of hours worked are multiplied by the hourly rate to arrive at gross pay. Gross pay is an intermediate step which is retained temporarily for late use.
2. Verifying. Since recording is usually a manual operation, it is important that recorded data be carefully checked for any errors. This operation is called verifying. For example, punched card and type reports are reread for correctness.
3. Duplicating. It is sometimes necessary or desirable to copy or duplicate data. This operation consists in reproducing data unto many forms or documents. Duplicating may be done while the data are being recorded manually, or it may be done afterwards, by some machine. For example, one may record by typing it, at the same time duplicating it using carbon paper. On the other hand, one may record a sales transaction by punching the data unto a card, and may then duplicate the card by using a duplicating machine.
4. Classifying. This operation separates data into various categories. Identifying are arranging items with like characteristics into groups or classes is called classifying. Sales data taken from a sales ticket may be classified by product sold, location of sales point, customer, sales clerk, or any other classification that the processing cycle may require. Classifying is usually done by shortened, predetermined method of abbreviation known as coding. The three types of codes used are: a) numeric – a person’s social security number or student id number, b) alphabetic – grades as A, B, and C or names of persons, and c) alphanumeric – automobile license plate or course and year.
5. Sorting. Arranging data in a specific order is called sorting. After the data are classified, it is usually necessary to arrange or rearrange them in a predetermined sequence to facilitate processing. Sorting is done in an alphabetic or a numeric order and the data item which determines the sorting is called the key. Numeric sorting usually requires less time than alphabetic sorting in machine-based processing systems and is therefore generally used. This operation is familiar in everyday life. As an example, the names in a telephone book are sorted into alphabetical order, employee records may be sorted according to employee’s last name or ID number.
6. Calculating. Arithmetic manipulation of the data is known as calculating. It is a crucial phase of data manipulation, because the outcome of this operation becomes part of the output. In the calculation of an employee’s pay, for example the total number of hours worked multiplied by the hourly wage rate would give the taxable gross earnings. Payroll deductions such as taxes, medicare, union dues and other deductions are then computed and subtracted from gross earnings to leave net or take-home earnings.
7. Summarizing and Reporting. In this operation, a collection of data is condensed and certain conclusions from the data are represented in a meaningful format. To be of value, data must often be condensed or sifted so that the resulting output reports will be clear, concise and effective. Reducing masses of data to a more usable form is called summarizing.
8. Merging. This operation takes two or more sets of data, all sets having been sorted by the same key, and puts then together to form a single sorted set of data. As an example, sales reports from different store branches are merge to form an overall sales report for the whole business establishment.
9. Storing. Placing similar data into files for future references is storing. Storage is done by any of the following methods: a) manual-such as in a ledger book, b) electromechanical-in the form of punched cards, and c) electronic-by magnetic tape, disk and main memory of the computer. Data should be stored only if the value of having them in the future exceeds the storage cost.
10. Retrieving. Recovering stored data and/or information when needed is the retrieving step. Retrieval methods range from searches made by file clerks to the use of quick-responding inquiry terminals that are connected directly to a computer. The computer, in turn, is connected directly to a mass-storage device that contains the information.
11. Feedback. Feedback is the comparison of the output(s) and the goal set in advance; and discrepancy is analyze, corrected, and fed back to the proper stage in the processing operation. The feedback step permits businesspersons to follow up on essential information and to attain worthwhile goals.