Common event contract
Fields that keep these queries reusable
- timestamp_utc, route_template, release, environment, and device_class
- metric_name, metric_value, unit, threshold_version, and passed
- session_id or approved account dimension only when the analysis requires it
Definitions before SQL
Decisions the query cannot make for you
- 1Use stable route templates instead of raw URLs or query strings.
- 2Version performance thresholds and preserve the original metric unit.
- 3Require sufficient samples before comparing releases, devices, or regions.
Recommended sequence
Build detection first, then diagnosis
Analysis patterns
Make the result explain a decision
Keep route and release together
A frontend regression becomes actionable when it can be isolated to a stable product surface and deployment boundary.
Preserve individual vitals
Report LCP, INP, and CLS separately beside a summary pass rate so one good metric cannot hide a different poor experience.
Protect sparse comparisons
Show sample count and complete observation windows before interpreting device, geography, or release segments.
Complete recipes
Copy the query, then validate the assumptions
Compare Core Web Vitals by Route and Release
Compare LCP, INP, and CLS samples by stable route and release while keeping the percentage of passing samples visible.
Which route and release has the weakest frontend performance?
See SQL and resultRank JavaScript Errors by Route and Release
Find frontend releases and routes with the most repeated JavaScript failures and affected sessions.
Which route and frontend release produces the broadest JavaScript error impact?
See SQL and resultMeasure SPA Navigation Latency by Route
Compare typical and tail client-side navigation time by destination route and frontend release.
Which destination routes have the slowest client-side navigation?
See SQL and resultCalculate Browser Long-Task Rate by Route
Measure main-thread blocking events and their total blocked time by route and frontend release.
Which routes and releases spend the most time in browser long tasks?
See SQL and resultFind Slow Frontend Resources by Host
Rank scripts, stylesheets, images, and API resources by tail duration, failures, and transferred bytes.
Which resource hosts and types are slowing or failing page loads?
See SQL and resultAdapt the event contract before the threshold
Keep the analysis pattern, but validate table names, field types, business definitions, time windows, and minimum-volume rules against your own events. Every published query is also planned and executed against an empty typed table with the pinned engine.