Chapter 15: Exchanging Data: Compression, Encryption and Hashing

A-level Computer ScienceOCR6 topicsHigher

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SQL Long-Answer Questions

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4 questions24 marks36 min

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6 marksdescribestandardOCR A

CS15-1 SQL queries: describe how SELECT, WHERE, ORDER BY and aggregate functions operates in retrieving all biology attempts above 80 percent, using precise OCR H446 terminology.

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6 marksexplainstandardOCR A

CS15-2 applied case: explain why SELECT, WHERE, ORDER BY and aggregate functions would affect retrieving all biology attempts above 80 percent, including one limitation or trade-off.

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6 markswritehardOCR A

CS15-3 task for SQL queries: write a response using SELECT, WHERE, ORDER BY and aggregate functions in retrieving all biology attempts above 80 percent; produce a syntactically valid SQL query.

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6 marksevaluatesynopticOCR A

CS15-4 synoptic judgement: evaluate the suitability of SELECT, WHERE, ORDER BY and aggregate functions for retrieving all biology attempts above 80 percent, comparing it with one credible alternative.

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14. Software Development: Assembly Language

16. Exchanging Data: Database Concepts

Key learning objectives

Understand the key principles behind Exchanging Data: Compression, Encryption and Hashing.
Apply these ideas to exam-style questions.
Recall the essential definitions and key terms.