lesson
Check every route
1 · Learn
A database is only useful when the data and questions are accurate. Test each item from the start and check it reaches the correct endpoint.
If an item could go either way because a question is vague, rewrite the question. If two items reach one endpoint, add a meaningful distinction instead of guessing which was intended.
2 · Worked example
Two red shapes cannot be separated by 'Is it red?' alone. I add a question about their different numbers of sides.
3 · Your turn
Why is testing just one shape not enough to prove a whole branching database works?
Check your answer
Other shapes use different routes. Each route may contain an error that the first test does not reach.
4 · Apply your learning
Swap a small database with a partner. Ask them to record each route using your exact questions, then revise one unclear question if needed.
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Use an adult-approved offline or school-managed application. Use invented data, original images and pretend identities. Paper models explain an idea but must be followed by suitable practical device work. Never enter real passwords or personal information in the working pad.
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