Hello students, welcome back to another Computer Science lesson. In today’s video, we are going to learn about file handling in APPEND mode, exactly according to the Cambridge O-Level Computer Science 2210 syllabus. By the end of this lesson, you will clearly understand what append mode is, why it is used, and how to write correct pseudocode for it in your exams.

File handling means storing data permanently in a file so that it can be used later, even after the program has ended. Unlike variables, which lose their values when the program stops running, files allow us to save data for long-term use. This is especially useful for storing information such as student records, examination marks, usernames, or any data that needs to be kept for future access.

Append mode is used when we want to add new data to the end of an existing file without removing or overwriting the old data. This is very useful in real-life situations. For example, if a school already has a file containing student names and a new student joins, we do not want to delete the existing records. Instead, we simply append the new student’s data to the same file. It is important to remember for exams that WRITE mode deletes old data, whereas APPEND mode keeps the existing data and adds new data at the end of the file.

Now let’s understand the given pseudocode step by step. The statement OPENFILE STUDENTFILE FOR APPEND opens the file in append mode. If the file already exists, the new data will be added at the end of the file, and if the file does not exist, it will be created automatically. Next, DECLARE DATA2 : STRING creates a string variable to store the data entered by the user. The statement OUTPUT "ENTER DATA TO APPEND" displays a message asking the user to enter the data, and INPUT DATA2 then stores the user’s input into the variable. The most important line is STUDENTFILE.APPEND(DATA2), which adds the contents of the variable to the end of the file while keeping the existing data unchanged. The message OUTPUT "DATA APPENDED SUCCESSFULLY" confirms that the data has been added, and finally, STUDENTFILE.CLOSE() closes the file to ensure the data is saved properly and system resources are released.

In exams, you should always use OPENFILE … FOR APPEND when you are asked to add data to a file. You must never forget to close the file, as this is a common mistake that can cost marks. Also, make sure to use clear variable names, correct data types, and write your pseudocode exactly in the Cambridge style.

To conclude, append mode allows us to safely add new data to an existing file without losing any previous information. It is a very important concept in file handling and is frequently tested in O-Level Computer Science examinations. If you understand when to use append mode and can write its pseudocode correctly, you will be well prepared to score full marks in file-handling questions.