The answer is to increase the TARGET ACCURACY value to 99. This works because TARGET ACCURACY directly controls the trade-off between search speed and result quality; a higher value forces the approximate vector search to examine more candidate vectors during the query phase, thereby improving recall by reducing the chance of missing relevant neighbors. On the Oracle Cloud Infrastructure Generative AI Professional 1Z0-1127 exam, this concept tests your understanding of how vector index parameters balance recall and performance—a common trap is confusing TARGET ACCURACY with neighbor partition settings, which primarily affect index structure rather than query-time candidate depth. A helpful memory tip is to think of TARGET ACCURACY as a "recall dial": turning it up toward 99 tightens the search net, catching more true positives without requiring a full index rebuild.
1Z0-1127 Practice Question: Building LLM Applications with RAG and Vector Search
This 1Z0-1127 practice question tests your understanding of building llm applications with rag and vector search. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
Exhibit
Refer to the exhibit.
```sql
-- Oracle Database 23ai AI Vector Search index creation
CREATE VECTOR INDEX doc_vec_idx ON documents(chunk_embedding)
ORGANIZATION NEIGHBOR PARTITIONS
DISTANCE COSINE
WITH TARGET ACCURACY 95
PARAMETERS (TYPE IVF, NEIGHBOR PARTITIONS 4);
```
A DBA has created the above vector index. After running queries, they observe that recall is lower than expected for approximate searches. Which change would most likely improve recall while maintaining query performance?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Increase the TARGET ACCURACY value to 99.
Option D is correct because increasing the TARGET ACCURACY parameter forces the index to consider more candidates, improving recall. Option A is wrong because increasing neighbor partitions may improve performance but not necessarily recall. Option B is wrong because changing to HNSW would alter the index type but may require more rebuild. Option C is wrong because reducing neighbor partitions reduces recall.
Key principle: OSPF neighbour adjacency depends on matching area, hello/dead timers, network type, and authentication — IP reachability alone is not enough.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✗
Change the index type from IVF to HNSW.
Why it's wrong here
While HNSW generally offers better recall, the question asks for a change within the current index context; TARGET ACCURACY is more direct.
✓
Increase the TARGET ACCURACY value to 99.
Why this is correct
A higher TARGET ACCURACY forces the approximate search to consider more vectors, increasing recall at the cost of some latency.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Increase the number of neighbor partitions (NEIGHBOR PARTITIONS) to 8.
Why it's wrong here
More partitions can improve parallelism but may not directly improve recall; recall is controlled by TARGET ACCURACY.
✗
Reduce the number of neighbor partitions to 2.
Why it's wrong here
Fewer partitions reduce the search space, likely lowering recall.
Common exam traps
Common exam trap: OSPF can fail even when IP connectivity looks correct
OSPF neighbour formation depends on matching areas, timers, network type, authentication and passive-interface behaviour. Do not choose an answer only because the devices can ping.
Detailed technical explanation
How to think about this question
OSPF questions usually test the details that control adjacency and route selection. Read the neighbour state, area, router ID and interface configuration before deciding what is wrong.
KKey Concepts to Remember
OSPF neighbours must agree on key parameters.
Router ID selection can affect neighbour relationships and LSDB output.
OSPF cost influences the preferred path.
A route can appear in OSPF information but not become the installed route.
TExam Day Tips
→Check area mismatch first when OSPF adjacency fails.
→Review passive interfaces when a network is advertised but no neighbour forms.
→Use show ip ospf neighbor and show ip route clues carefully.
Key takeaway
OSPF neighbour adjacency depends on matching area, hello/dead timers, network type, and authentication — IP reachability alone is not enough.
Real-world example
How this comes up in practice
A network engineer at a university connects two campus buildings via a fibre link. Both routers run OSPF, but no adjacency forms — even though both routers can ping each other. The engineer finds one router is in area 0 and the other in area 1. OSPF adjacency requires matching area numbers, hello/dead timers, and network type. IP reachability alone is not enough.
What to study next
Got this wrong? Here's your next step.
Review OSPF neighbour requirements — matching area type, hello and dead timers, network type, stub flags, and authentication. Study show ip ospf neighbor states (INIT, 2-WAY, FULL). Then practise related 1Z0-1127 OSPF questions on adjacency and route selection.
Building LLM Applications with RAG and Vector Search — This question tests Building LLM Applications with RAG and Vector Search — OSPF neighbours must agree on key parameters..
What is the correct answer to this question?
The correct answer is: Increase the TARGET ACCURACY value to 99. — Option D is correct because increasing the TARGET ACCURACY parameter forces the index to consider more candidates, improving recall. Option A is wrong because increasing neighbor partitions may improve performance but not necessarily recall. Option B is wrong because changing to HNSW would alter the index type but may require more rebuild. Option C is wrong because reducing neighbor partitions reduces recall.
What should I do if I get this 1Z0-1127 question wrong?
Review OSPF neighbour requirements — matching area type, hello and dead timers, network type, stub flags, and authentication. Study show ip ospf neighbor states (INIT, 2-WAY, FULL). Then practise related 1Z0-1127 OSPF questions on adjacency and route selection.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
OSPF neighbours must agree on key parameters.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This 1Z0-1127 practice question is part of Courseiva's free Oracle 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 1Z0-1127 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.