CS Database Management & SQL 4

Question 1

A database administrator runs 'GRANT SELECT ON customers TO analyst;'. What does this accomplish?

Accepted Answer

Gives the analyst permission to read the customers table

Answer

GRANT assigns the SELECT privilege on the table to the specified user or role.

Question 2

What problem does normalization primarily aim to reduce?

Accepted Answer

Data redundancy and update anomalies

Answer

Normalization organizes data to minimize redundancy and prevent insert, update, and delete anomalies.

Question 3

Which SQL function would you use to replace NULL values with a default in a result set?

Accepted Answer

COALESCE

Answer

COALESCE returns the first non-NULL value in its argument list.

Question 4

A query plan shows a full table scan on a large table filtered by a WHERE clause on 'email'. What is the most likely fix?

Accepted Answer

Create an index on the email column

Answer

An index on the filtered column lets the optimizer avoid scanning every row.

Question 5

Which statement correctly describes a database view?

Accepted Answer

A stored query that presents data as a virtual table

Answer

A view is a named, stored query whose results are computed when the view is referenced.

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