Databricks-Spark-Assoc Using Spark SQL Practice Question
Which command is used to display the logical and physical execution plans for a given Spark SQL query?
⚠ Common exam trap
Test-takers frequently confuse the EXPLAIN command with DESCRIBE or SHOW commands, failing to realize that EXPLAIN specifically outputs the Catalyst optimizer's execution plans.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
EXPLAIN SELECT * FROM table
The 'EXPLAIN' command is the essential tool for inspecting the Catalyst query optimizer's work. It provides a breakdown of the logical plan (the raw representation of the query), the analyzed plan, the optimized plan, and the physical plan (how Spark will actually execute the tasks). Understanding this output is crucial for performance tuning, as it reveals how Spark handles joins, filters, and projections before the query actually runs on the distributed cluster nodes.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
SHOW PLAN
Why it's wrong here
There is no 'SHOW PLAN' command in Spark SQL. Users must use the 'EXPLAIN' keyword. 'SHOW' is typically used for listing tables, schemas, or views, not for inspecting the internal execution plans of query operations, which are the domain of the optimizer's diagnostic tools.
- ✗
DESCRIBE QUERY
Why it's wrong here
The 'DESCRIBE' command is used to view metadata about tables or columns. It provides information about the schema, data types, and partitioning. It does not provide any insight into the execution plan or the optimization steps that the Spark engine takes to resolve a SQL query.
- ✓
EXPLAIN SELECT * FROM table
Why this is correct
The 'EXPLAIN' command is the standard way to inspect Spark's query execution plans. It helps developers understand how the Catalyst optimizer parses and plans the query, allowing them to identify bottlenecks, such as unnecessary shuffles or full table scans, before executing the actual data-intensive operations on the large dataset.
- ✗
DEBUG SELECT * FROM table
Why it's wrong here
The 'DEBUG' command is not a valid SQL keyword in Spark. Spark uses 'EXPLAIN' for diagnostic purposes. 'DEBUG' might exist in other programming tools or IDEs, but it has no meaning within the Spark SQL execution engine's syntax for inspecting execution plans or investigating query performance issues.
About these practice questions
One of 295 original Databricks-Spark-Assoc practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Databricks exam blueprint
This Databricks-Spark-Assoc practice question is part of Courseiva's free Databricks certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the Databricks-Spark-Assoc exam.