IGCSE CS SQL and Databases questions

What is a database?

• A collection of random data
• A structured collection of data
• A type of programming language
• A hardware component

Answer explanation

A database organizes data into a structured format for easy retrieval.

In a database, what is a table?

• A single data value
• A collection of records
• A type of query
• A software tool

Answer explanation

Tables store data in rows (records) and columns (fields).

What does SQL stand for?

• Simple Query Language
• Structured Query Language
• System Query Logic
• Sequential Query Layer

Answer explanation

SQL is Structured Query Language, used to manage databases.

Which SQL command retrieves data from a database?

• INSERT
• SELECT
• UPDATE
• DELETE

Answer explanation

SELECT retrieves data from one or more tables.

What is a primary key in a database?

• A duplicate field
• A unique identifier for a record
• A sorted column
• A temporary value

Answer explanation

A primary key uniquely identifies each record in a table.

Which SQL clause specifies conditions for filtering data?

• FROM
• WHERE
• ORDER BY
• GROUP BY

Answer explanation

WHERE filters rows based on specified conditions.

What is the purpose of the 'FROM' clause in SQL?

• To sort data
• To specify the table to query
• To group data
• To join tables

Answer explanation

FROM identifies the table(s) from which data is retrieved.

Which SQL command adds new data to a table?

• SELECT
• INSERT
• UPDATE
• DELETE

Answer explanation

INSERT adds new records to a database table.

What does the 'ORDER BY' clause do in SQL?

• Filters data
• Sorts the result set
• Groups data
• Joins tables

Answer explanation

ORDER BY sorts query results, e.g., alphabetically or numerically.

Which data type in SQL stores whole numbers?

• VARCHAR
• INTEGER
• BOOLEAN
• DATE

Answer explanation

INTEGER stores whole numbers without decimals.