Question 120
The reliability team at Silverline Insurance is closing a corrective-action ticket for this ML failure: A purchase prediction team scans a five-year BigQuery click table without date filters on every experiment and repeatedly incurs avoidable full-table reads. What measured outcome provides the strongest check that this problem is resolved?
Explanation
Correct Answer
Query plans show partition pruning and reduced scanned bytes while experiment outputs retain the expected record counts. This controlled observation specifically validates the proposed remedy: Partition the training table on event date and cluster on useful access keys, then apply explicit partition filters in training queries. It addresses the documented failure at Silverline Insurance: A purchase prediction team scans a five-year BigQuery click table without date filters on every experiment and repeatedly incurs avoidable full-table reads.
Incorrect Answers
The held-out data preserves real zeros as distinct from missing readings and passes predeclared data-quality checks. This is evidence for a different corrective change: Define per-feature missingness rules and train-only imputers with explicit missing indicators where justified. That other change addresses: An ML feed has meaningful null values but a preprocessing pipeline replaces every missing numeric measurement with zero, changing business semantics. It does not validate the specific Silverline Insurance remediation for: A purchase prediction team scans a five-year BigQuery click table without date filters on every experiment and repeatedly incurs avoidable full-table reads. The necessary check instead is: Query plans show partition pruning and reduced scanned bytes while experiment outputs retain the expected record counts.
A batch loader retrieves images by reference with valid labels and no redundant large inline binary columns. This is evidence for a different corrective change: Keep image objects in Cloud Storage and maintain governed labels and object references in a queryable catalog. That other change addresses: An image classification team stores training images directly in BigQuery rows as base64 strings, making batch loading inefficient and costly. It does not validate the specific Silverline Insurance remediation for: A purchase prediction team scans a five-year BigQuery click table without date filters on every experiment and repeatedly incurs avoidable full-table reads. The necessary check instead is: Query plans show partition pruning and reduced scanned bytes while experiment outputs retain the expected record counts.
The full-scale integration finishes without notebook OOM and matches checksums on a validated sample. This is evidence for a different corrective change: Use a suitable distributed preprocessing engine such as Spark on Dataproc for the large shuffle and persist curated outputs. That other change addresses: A data science team attempts to join terabytes of distributed logs inside a single notebook's pandas process and repeatedly exhausts memory. It does not validate the specific Silverline Insurance remediation for: A purchase prediction team scans a five-year BigQuery click table without date filters on every experiment and repeatedly incurs avoidable full-table reads. The necessary check instead is: Query plans show partition pruning and reduced scanned bytes while experiment outputs retain the expected record counts.