Question 360
At Juniper Media, the streaming service databases team maintains a content subscriptions and audience reporting platform with requirements for traffic peaks and isolated customer information. The acceptance review requires independent evidence for: A monitoring team assumes all slow requests come from missing indexes but Query Store identifies a sudden plan regression without a schema change. Which observed result BEST proves the intended problem is corrected?
Explanation
Correct Answer
The affected query returns to the approved runtime profile and a forced-plan health check detects no unsupported plan behavior. That observable result supports resolution of: A monitoring team assumes all slow requests come from missing indexes but Query Store identifies a sudden plan regression without a schema change. The corresponding corrective change is: Use Query Store performance evidence and a supported plan forcing or regression correction after validating applicability. The Juniper Media reviewer can distinguish demonstrated database behavior from an untested change claim.
Incorrect Answers
The targeted query uses an effective seek or narrower scan with fewer logical reads and acceptable write overhead. That result is evidence for another corrective change: Evaluate an appropriate nonclustered index using predicates, selectivity and maintenance costs, then test the actual execution plan. The alternative problem is: A reporting query scans a very large transaction table for a selective customer ID because the table lacks a useful access path. The current Juniper Media issue is instead: A monitoring team assumes all slow requests come from missing indexes but Query Store identifies a sudden plan regression without a schema change. Its decisive acceptance evidence would be: The affected query returns to the approved runtime profile and a forced-plan health check detects no unsupported plan behavior.
The stabilized query uses an appropriate plan for representative parameter sets and duration variance falls without global index rebuilds. That result is evidence for another corrective change: Compare Query Store plans and runtime statistics to isolate parameter sensitivity and consider a supported plan or query correction. The alternative problem is: A stored procedure occasionally chooses an inefficient execution plan after parameter changes and the team blindly rebuilds every table index. The current Juniper Media issue is instead: A monitoring team assumes all slow requests come from missing indexes but Query Store identifies a sudden plan regression without a schema change. Its decisive acceptance evidence would be: The affected query returns to the approved runtime profile and a forced-plan health check detects no unsupported plan behavior.
The actual plan demonstrates corrected cardinality and reduced work for the representative parameter set. That result is evidence for another corrective change: Compare estimated and actual plans with row counts and resource metrics to identify estimation or join-selection problems. The alternative problem is: A SQL DBA sees an estimated execution plan only and concludes a query cannot have cardinality estimation errors at runtime. The current Juniper Media issue is instead: A monitoring team assumes all slow requests come from missing indexes but Query Store identifies a sudden plan regression without a schema change. Its decisive acceptance evidence would be: The affected query returns to the approved runtime profile and a forced-plan health check detects no unsupported plan behavior.