lesson
State the question precisely
1 · Learn
A query can combine conditions. Category is nature AND pages exceed 50 means both must be true. Using OR means at least one of the conditions is enough.
Check results against known sample records. A nature book with 30 pages fails the AND query but satisfies the OR query because it meets the category condition.
2 · Worked example
Invented book A: nature, 80 pages; B: nature, 30 pages; C: history, 90 pages. The AND query returns only A. The OR query returns A, B and C.
3 · Your turn
For the stated records, which match 'nature AND more than 50 pages'? Would C match the OR version?
Check your answer
Only A matches the AND query. Yes, C matches OR because its page count exceeds 50.
4 · Apply your learning
Write two different queries on your invented collection and predict their results before running them. Investigate any mismatch.
Adult guidance and safety
Use adult-approved offline or school-managed tools, invented data and original media. Keep projects private unless sharing is explicitly approved. Paper traces support, but do not replace, practical programming and saved digital work. No real passwords or personal records belong in these exercises.
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Check a calculation · Year 5 onward
Use this only when your teacher or adult allows a calculator for the task. Show your thinking first. It does not replace mental or written arithmetic and does not mark your lesson answer.
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