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Computer science · lesson 1 of 4

Tables, rows and keys

A relation represented as rows with named columns.

University8 practice questionsNotes + worked examples
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Learn the ideas

Prerequisites: Basic computing and simple data tables.

Table

A relation represented as rows with named columns.

Primary key

A constraint identifying each row uniquely.

Foreign key

A value constrained to reference a key in another relation.

Schema

The defined structure, fields and constraints of stored data.

Worked examples

Example 1

Which term best matches this description: A relation represented as rows with named columns.

Table is the matching concept in this lesson.

Table

Example 2

Which term best matches this description: A constraint identifying each row uniquely.

Primary key is the matching concept in this lesson.

Primary key

Check your understanding

8 questions

Decimals or fractions are accepted for numeric answers. Proofs and written responses use sample answers and require human marking. This is practice, not a protected examination.

1 Which term best matches this description: A relation represented as rows with named columns.

Show answer and explanation

Table

Table is the matching concept in this lesson.

2 Which term best matches this description: A constraint identifying each row uniquely.

Show answer and explanation

Primary key

Primary key is the matching concept in this lesson.

3 Which concept would you apply first in a situation where a value constrained to reference a key in another relation.

Show answer and explanation

Foreign key

The scenario directly calls for Foreign key.

4 Name the concept described as: The defined structure, fields and constraints of stored data.

Show answer and explanation

Schema

The intended concept is Schema.

5 Which statement about Table is most accurate?

Show answer and explanation

A relation represented as rows with named columns.

The definition in the lesson notes gives the required condition.

6 Explain one important difference between Table and Primary key.

Sample answer and marking guidance

Table: A relation represented as rows with named columns. Primary key: A constraint identifying each row uniquely.

Credit a clear distinction using both definitions and an appropriate example if supplied.

7 Give a short example showing how Foreign key would be used in practice.

Sample answer and marking guidance

A valid example should demonstrate this idea: A value constrained to reference a key in another relation.

Credit a relevant scenario that applies the concept rather than merely naming it.

8 Summarize why Schema matters in the lesson “Tables, rows and keys”.

Sample answer and marking guidance

Schema matters because The defined structure, fields and constraints of stored data.

Credit the core purpose, scope and any important limitation from the notes.

Further reading and review references

These are reference links, not copied exercises, institutional endorsement or proof of independent review.