CAIC Database Administration 3

Question 1

An AI system must maintain a consistent snapshot of training data while a bulk import job is running. Which PostgreSQL transaction isolation level provides this guarantee without blocking the import?

Accepted Answer

REPEATABLE READ

Answer

REPEATABLE READ ensures the transaction sees a consistent snapshot taken at the start of the transaction, preventing non-repeatable reads without blocking concurrent writes.

Question 2

A vector database stores 1 billion 768-dimensional embeddings. Which storage optimization reduces disk usage while maintaining acceptable recall for approximate nearest neighbor search?

Accepted Answer

Applying product quantization (PQ) to compress vectors

Answer

Product quantization divides vectors into sub-vectors and quantizes each, achieving 4x–32x compression with minimal recall loss compared to storing full-precision floats.

Question 3

An AI consultant discovers that a nightly ETL pipeline runs 47 sequential INSERT statements instead of a bulk load. What is the most impactful fix?

Accepted Answer

Replace sequential INSERTs with a single COPY or bulk insert operation

Answer

Bulk load operations like COPY bypass per-row overhead and transaction commits, loading data orders of magnitude faster than sequential individual INSERTs.

Question 4

A feature store uses a key-value cache (Redis) in front of PostgreSQL. After a model update changes feature semantics, which cache strategy prevents stale features from reaching the model?

Accepted Answer

Cache-aside pattern with write-through invalidation on feature update

Answer

Write-through invalidation explicitly deletes or overwrites cache entries when the underlying feature data changes, ensuring the model always receives current values.

Question 5

Which database concept ensures that if an AI training job crashes mid-batch, the database returns to the last consistent state without manual intervention?

Accepted Answer

Atomicity enforced by transaction rollback

Answer

Atomicity guarantees that a transaction is either fully committed or fully rolled back, so a crash mid-batch leaves the database at the last successful commit.

(CAIC) Certified AI Consultant Practice Test

(CAIC) Certified AI Consultant Practice Test

CAIC Database Administration 3