Algorithm Design And Problem-solving: Understand The Need For Validation Checks To Be Made On Input Data And The Different Types Of Validation Check (Copy)
| Concept | Explanation |
|---|---|
| Validation | Checking that input data is reasonable and sensible |
| Purpose | Prevents incorrect or meaningless data entering a system |
| When Used | At data entry stage before processing |
| Result | Improves accuracy, reliability, and safety of outputs |
Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change O Level And IGCSE Computer Science Full Scale Course
| Why Validation Is Needed | Reason |
|---|---|
| Accuracy | Prevents wrong results |
| Reliability | Ensures system works correctly |
| Error Prevention | Stops crashes or logical errors |
| Data Quality | Ensures meaningful processing |
| User Guidance | Forces correct data entry |
Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change O Level And IGCSE Computer Science Full Scale Course
| Validation Check | What It Checks | Example |
|---|---|---|
| Range Check | Value is within limits | Age between 0 and 120 |
| Length Check | Correct number of characters | Password ≥ 8 characters |
| Type Check | Correct data type | Age must be an integer |
| Format Check | Matches required pattern | Email contains @ |
| Presence Check | Data is not left blank | Name field not empty |
Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change O Level And IGCSE Computer Science Full Scale Course
| Additional Validation Checks | Purpose | Example |
|---|---|---|
| Limit Check | Value does not exceed limit | Max marks = 100 |
| Check Digit | Detects input errors | ISBN number |
| Lookup Check | Matches list of valid values | Country selection list |
| Consistency Check | Data matches related input | End date after start date |
Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change O Level And IGCSE Computer Science Full Scale Course
| Validation vs Verification | Validation | Verification |
|---|---|---|
| Purpose | Is data sensible? | Is data entered correctly? |
| Focus | Meaningfulness | Accuracy of entry |
| Example | Age not negative | Password retyped correctly |
Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change O Level And IGCSE Computer Science Full Scale Course
| Exam Key Phrases | Use These |
|---|---|
| Validation | “Checks data is sensible and reasonable” |
| Range | “Ensures value is within limits” |
| Type | “Ensures correct data type” |
| Presence | “Ensures data is not empty” |
| Difference | “Validation checks sense, verification checks accuracy” |
Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change O Level And IGCSE Computer Science Full Scale Course