CERTIFIED-DATA-ANALYST-ASSOCIATE Question #51: Real Exam Question with Answer & Explanation

Question

Which statement about subqueries is correct?

Options

• ASubqueries are not available in Databricks SQL
• BSubqueries can be used like other user-defined functions to transform data into different data
• CSubqueries can retrieve data without requiring the creation of a table or view.
• DSubqueries can be used like other built-in functions to transform data into different data types.

Explanation

Option C is correct because a subquery is a query nested inside another query (SELECT, INSERT, UPDATE, or DELETE), allowing you to fetch and filter data on the fly without persisting it as a table or view - the result exists only for the duration of the outer query.

Why the distractors are wrong:

• A is false - Databricks SQL fully supports subqueries, including scalar, correlated, and EXISTS subqueries.
• B is false - subqueries are not user-defined functions (UDFs); UDFs are named, reusable routines you register, while subqueries are inline query expressions.
• D is false - subqueries do not transform data types; that's the role of casting functions like CAST() or TRY_CAST(). Subqueries return result sets, not type conversions.

Memory tip: Think of a subquery as a temporary, throwaway query - it gives you data in the moment without leaving anything behind. If nothing is created and nothing persists, it's a subquery doing its job.

No community discussion yet for this question.