DP-300 PAGELATCH_EX Practice Question
You are troubleshooting a performance issue on an Azure SQL Database. The database is experiencing high PAGELATCH_EX waits. Which TWO measures can help reduce these waits?
⚠ Common exam trap
DP-300 often tests the confusion between PAGELATCH_EX and PAGELATCH_SH or LCK waits, and may include distractors like snapshot isolation which addresses locking, not latching.
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
✓
Partition the table to distribute inserts
Option C is correct because PAGELATCH_EX waits are commonly caused by last-page insert contention on monotonically increasing keys (e.g., IDENTITY), and partitioning the table across multiple partitions/files spreads those inserts across different pages, eliminating the hot last-page latch. Option D is correct because the OPTIMIZE_FOR_SEQUENTIAL_KEY index option, introduced in SQL Server 2019/Azure SQL Database, specifically mitigates last-page insert PAGELATCH_EX contention by managing the insert into the index's last page more efficiently. Option A is not applicable because hash or round-robin distribution is a dedicated SQL pool (formerly SQL DW) table design concept, not a remedy for PAGELATCH_EX in Azure SQL Database. Option B is wrong because increasing MAXDOP does not reduce page latch contention and can even worsen it by increasing concurrent insert pressure. Option E is wrong because enabling snapshot isolation addresses blocking/locking (LCK waits) and read-write contention, not PAGELATCH_EX waits on data pages.
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 a hash distribution or round-robin distribution in a table design
Why it's wrong here
Hash or round-robin distribution applies to Azure Synapse dedicated SQL pools, not Azure SQL Database, so it cannot reduce PAGELATCH_EX waits there. It is tempting because distribution design genuinely relieves latch contention in massively parallel warehouses, but Azure SQL Database uses a different storage engine where that mechanism does not exist.
- ✗
Increase MAXDOP for the queries
Why it's wrong here
Increasing MAXDOP spreads a query across more schedulers, which does not relieve PAGELATCH_EX waits; those arise from concurrent threads contending on the same in-memory page, typically insert-heavy workloads hitting the last page of a narrow index. MAXDOP tuning addresses parallelism-related waits such as CXPACKET, so it would be the right lever for a query suffering from skewed parallel execution.
- ✓
Partition the table to distribute inserts
Why this is correct
PAGELATCH_EX waits arise from concurrent inserts contending on the last page of an ascending index. Partitioning the table across multiple filegroups or partition ranges spreads inserts over several hot pages, reducing that contention and therefore the exclusive page-latch waits the database is experiencing.
- ✓
Use OPTIMIZE_FOR_SEQUENTIAL_KEY index option
Why this is correct
PAGELATCH_EX waits arise from concurrent inserts contending on the last-page insert point of monotonically increasing keys. OPTIMIZE_FOR_SEQUENTIAL_KEY changes the latch acquisition behaviour for such indexes, reducing this contention without altering the query plan or schema.
- ✗
Enable snapshot isolation level
Why it's wrong here
Snapshot isolation removes reader-writer blocking, but PAGELATCH_EX waits are in-memory page-latch contention on hot last-page inserts, not lock waits, so it changes nothing. It is tempting because it addresses blocking, and it would be correct for reducing reader-writer lock contention in a read-heavy OLTP workload.
Go deeper
Related to this question
Learn chapter
Managing Environment Configurations and Resource Governance
Key term
Azure SQL Performance Tuning
Azure SQL Performance Tuning is the process of optimizing the speed and efficiency of queries and database operations in Microsoft Azure SQL Database or SQL Managed Instance to reduce latency and improve throughput.
About these practice questions
Courseiva writes every DP-300 question from scratch — 574 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. 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 Microsoft exam blueprint
This DP-300 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-300 exam.