WGU D432 Data Systems
Administration Performance
Assessment 2026/2027 – Verified Q&As
with Detailed Rationales (Test Bank
Bundle - 47 Questions)
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*QUESTION 1:*
A database administrator is responsible for daily backups. Which type of backup captures only the
changes made since the last full backup?
A) Differential backup
B) Incremental backup
C) Transaction log backup
D) Full backup
> 🎯 *CORRECT ANSWER:* A) Differential backup
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* A differential backup captures all changes since the last full backup.
> * *Why Distractors Fail:* Incremental captures changes since the last backup of any type; log backups
are for point-in-time.
> * *Core Takeaway:* Differential backups save changes since the last full backup.
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,*QUESTION 2:*
A system administrator is monitoring database performance. Which metric is most indicative of a
potential bottleneck?
A) High disk I/O wait time
B) Low CPU usage
C) High memory availability
D) Low network latency
> 🎯 *CORRECT ANSWER:* A) High disk I/O wait time
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* High I/O wait indicates the storage subsystem cannot keep up.
> * *Why Distractors Fail:* Low CPU and memory availability are good; low latency is not a bottleneck.
> * *Core Takeaway:* Disk I/O is a common performance bottleneck.
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*QUESTION 3:*
A DBA needs to restore a database to a specific point in time. Which backup type is required?
A) Transaction log backups
B) Differential backups
C) Full backups only
D) Filegroup backups
> 🎯 *CORRECT ANSWER:* A) Transaction log backups
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* Log backups allow point-in-time recovery.
> * *Why Distractors Fail:* Full and differential backups cannot restore to a specific time.
> * *Core Takeaway:* Transaction logs enable point-in-time recovery.
, ---
*QUESTION 4:*
A database is experiencing long query execution times. What is the most effective initial action?
A) Check for missing indexes
B) Add more memory
C) Upgrade the CPU
D) Reinstall the database
> 🎯 *CORRECT ANSWER:* A) Check for missing indexes
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* Missing indexes are a common cause of slow queries.
> * *Why Distractors Fail:* Hardware upgrades and reinstallation are drastic and may not address the
root cause.
> * *Core Takeaway:* Check indexes first for performance issues.
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*QUESTION 5:*
A database administrator is implementing a high-availability solution. Which feature provides automatic
failover?
A) Database mirroring
B) Log shipping
C) Database snapshots
D) Backup and restore
> 🎯 *CORRECT ANSWER:* A) Database mirroring
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* Mirroring provides automatic failover to a standby server.
Administration Performance
Assessment 2026/2027 – Verified Q&As
with Detailed Rationales (Test Bank
Bundle - 47 Questions)
---
*QUESTION 1:*
A database administrator is responsible for daily backups. Which type of backup captures only the
changes made since the last full backup?
A) Differential backup
B) Incremental backup
C) Transaction log backup
D) Full backup
> 🎯 *CORRECT ANSWER:* A) Differential backup
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* A differential backup captures all changes since the last full backup.
> * *Why Distractors Fail:* Incremental captures changes since the last backup of any type; log backups
are for point-in-time.
> * *Core Takeaway:* Differential backups save changes since the last full backup.
---
,*QUESTION 2:*
A system administrator is monitoring database performance. Which metric is most indicative of a
potential bottleneck?
A) High disk I/O wait time
B) Low CPU usage
C) High memory availability
D) Low network latency
> 🎯 *CORRECT ANSWER:* A) High disk I/O wait time
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* High I/O wait indicates the storage subsystem cannot keep up.
> * *Why Distractors Fail:* Low CPU and memory availability are good; low latency is not a bottleneck.
> * *Core Takeaway:* Disk I/O is a common performance bottleneck.
---
*QUESTION 3:*
A DBA needs to restore a database to a specific point in time. Which backup type is required?
A) Transaction log backups
B) Differential backups
C) Full backups only
D) Filegroup backups
> 🎯 *CORRECT ANSWER:* A) Transaction log backups
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* Log backups allow point-in-time recovery.
> * *Why Distractors Fail:* Full and differential backups cannot restore to a specific time.
> * *Core Takeaway:* Transaction logs enable point-in-time recovery.
, ---
*QUESTION 4:*
A database is experiencing long query execution times. What is the most effective initial action?
A) Check for missing indexes
B) Add more memory
C) Upgrade the CPU
D) Reinstall the database
> 🎯 *CORRECT ANSWER:* A) Check for missing indexes
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* Missing indexes are a common cause of slow queries.
> * *Why Distractors Fail:* Hardware upgrades and reinstallation are drastic and may not address the
root cause.
> * *Core Takeaway:* Check indexes first for performance issues.
---
*QUESTION 5:*
A database administrator is implementing a high-availability solution. Which feature provides automatic
failover?
A) Database mirroring
B) Log shipping
C) Database snapshots
D) Backup and restore
> 🎯 *CORRECT ANSWER:* A) Database mirroring
> 💡 *CLINICAL RATIONALE:*
> * *Why It's Right:* Mirroring provides automatic failover to a standby server.
