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SingaporeComputer ScienceQuick questions
Data, Information and Databases
Quick questions on SQL data definition and constraints explained: H2 Computing
4short Q&A pairs drawn directly from our worked dot-point answer. For full context and worked exam questions, read the parent dot-point page.
What are choosing data types?Show answer
The type fixes what a column may hold and how it is stored:
What are constraints that enforce rules?Show answer
Constraints are rules the database guarantees:
What is q1?Show answer
Which constraint guarantees a column has no duplicate values but is not the primary key? [1 mark]
What is q2?Show answer
Why store a price as DECIMAL rather than as a floating-point type? [2 marks]
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