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Paper 2
Databases and SQL
Both
Structured data helps businesses make decisions.
Key Facts
- Databases improve data accuracy and reduce duplication.
- Validation checks data type, range, or format.
- Verification ensures data is entered correctly.
Topics Covered
Tables and Keys
What you need to know
- •Fields are columns, records are rows.
- •Primary keys uniquely identify records.
Exam Tips
- Explain why primary keys prevent duplicates.
SQL Queries
What you need to know
- •Use SELECT, FROM, WHERE to query data.
- •Use ORDER BY for sorting and AND/OR for conditions.
Exam Tips
- Remember to use quotation marks for text values.
Normalisation
What you need to know
- •Remove repeated data and split into linked tables.
- •Use foreign keys to connect tables.
Exam Tips
- Explain how normalisation reduces redundancy.
Key Terms
primary key
A unique identifier for each record.
foreign key
A field that links to a primary key in another table.
SQL
Structured Query Language used to access data.
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Common Exam Questions
Write an SQL query to select students with scores above 80.
3 markseasyPaper 2
Model Answer
SELECT * FROM Students WHERE Score > 80;
What examiners want to see
- ✓Correct SELECT
- ✓Correct condition
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