DP-203 Develop data processing Practice Question
Your organization uses Azure Synapse Analytics dedicated SQL pool to store sales data. You need to design a data loading process for a nightly batch that inserts new rows and updates existing rows based on the business key. The table has a clustered columnstore index. Which approach minimizes table fragmentation?
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
✓
Create a staging table, load data, then use CTAS and partition switching to replace the target partition.
Using a staging table with CREATE TABLE AS SELECT (CTAS) and then switching partitions replaces the entire partition without individual row modifications, which minimizes fragmentation in a clustered columnstore index. Option A (UPDATE and INSERT) is wrong because individual updates cause columnstore fragmentation. Option B (DELETE and INSERT in a single transaction) also involves row-level changes that fragment columnstore. Option C (MERGE) is wrong because MERGE operations on columnstore indexes cause significant fragmentation due to row-by-row modifications.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Use UPDATE for existing rows and INSERT for new rows.
Why it's wrong here
UPDATE on columnstore causes fragmentation.
- ✗
Use DELETE and INSERT statements in a single transaction.
Why it's wrong here
Individual row operations fragment columnstore.
- ✗
Use a MERGE statement to perform upserts.
Why it's wrong here
MERGE causes row-by-row operations and fragmentation.
- ✓
Create a staging table, load data, then use CTAS and partition switching to replace the target partition.
Why this is correct
CTAS rebuilds the partition, minimizing fragmentation.
Go deeper
Related to this question
About these practice questions
One of 760 original DP-203 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 by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DP-203 practice question is part of Courseiva's free Microsoft 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 DP-203 exam.