National 5 Computing Science

Free revision guides

Software design and development

• Input validation: how to get all 4 marksN5 Computing Science input validation explained: why IF loses marks, the conditional loop that gains them, and the four things the marker looks for.
• Running total within a loopN5 Computing Science running total explained: set the total to 0 before the loop, add inside it, use it after. With the mistakes that lose marks.
• round, random and length: writing the whole callN5 Computing Science predefined functions: how to write round and random in full, with brackets and the right parameters, to gain every mark.
• Choosing the most suitable data typeN5 Computing Science data types: integer, real, character, string and Boolean, and why a phone number is a string. The traps the examiners keep seeing.
• Evaluating a program: answers that gain the markN5 Computing Science evaluation: efficiency, readability and robustness. Why learned-by-heart answers lose marks, and how to refer to the code instead.
• Concatenation: joining strings for the markN5 Computing Science concatenation: what it means, how to write it in reference language and Python, and why 'adding strings' does not gain the mark.
• Iterative development: describing going backN5 Computing Science iterative development: the six phases, and how to describe going back to an earlier phase in a way that gains the mark.
• Testing: test data and test tablesN5 Computing Science testing: normal, extreme and exceptional test data, filling in a test table, and the answers that gain the mark.

Computer systems

• Inside the processor: ALU, control unit and registersN5 Computing Science computer architecture: the job of the ALU, control unit, registers and buses, and how the exam asks about them inside programming questions.
• Compiler or interpreter? Spotting the cluesN5 Computing Science translators: how a compiler and an interpreter differ, and the clues in a question that tell you which one is meant.

Database design and development

• SQL with two tables: the equi-joinN5 Computing Science SQL: how to write a SELECT query that uses two linked tables, the equi-join in WHERE, and the mistakes that cost marks.
• SQL UPDATE and INSERT without losing marksN5 Computing Science SQL: the structure of UPDATE and INSERT statements, changing more than one field, and why a missing WHERE changes every record.
• Referential integrity: explaining it for the markN5 Computing Science referential integrity: what it means, why a record is rejected, and why writing just the words 'referential integrity' gains no mark.
• End-user and functional requirementsN5 Computing Science: the difference between end-user and functional requirements for a database or website, and why repeating the user's words loses the mark.

Web design and development

• End-user and functional requirementsN5 Computing Science: the difference between end-user and functional requirements for a database or website, and why repeating the user's words loses the mark.
• CSS classes and external style sheetsN5 Computing Science CSS: writing a class rule and using it in HTML, the benefit of an external style sheet, and how to read HTML and CSS together.
• Absolute and relative addressesN5 Computing Science hyperlinks: the difference between absolute and relative addresses, when to use each, and how to write a path into a folder.
• Making a sound file smallerN5 Computing Science file formats: how to reduce the size of a sound file without making it shorter, WAV and MP3 compared, and the answers that do not gain the mark.
• Testing: test data and test tablesN5 Computing Science testing: normal, extreme and exceptional test data, filling in a test table, and the answers that gain the mark.

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