Query Performance Analyzer

Inspect how IoT query shape, indexes, rollups, and cache choices change plan cost.

animation
databases
query-optimization
performance
time-series
iot
Interactive query performance analyzer showing time pruning, index access, filtering, sorting, joins, rollups, cache effects, rows scanned, rows returned, payload size, and estimated latency.
Interactive animation IoT data Query plans

Query Performance Analyzer

Follow one IoT query from request to result. Change the workload, data tier, index shape, and cache path to see why a fast dashboard starts with bounded predicates and visible plan evidence.

Plan shape Index range on rollup
Estimated latency 42 ms
Rows scanned 18.4K
Question Name the read path

Latest value, bounded window, rollup, join, replay, and export queries do different work.

Bound Constrain time first

Normal dashboards and APIs should avoid scanning old history without a reason.

Plan Match predicates to storage

Partition pruning and indexes only help when the query exposes the matching columns.

Evidence Record rows and freshness

Fast results still need row counts, cache age, quality fields, and a clear result budget.

Animated query path

The request is classified before the planner can choose a useful access path.

Stage 1 of 6
Query execution path and row funnel A query token moves through request, planner, time pruning, access path, work, and return stages. Bars below compare total rows, time-pruned rows, scanned rows, and returned rows. Request family Planner stats Prune time Access index/scan Work sort/join Return payload Total rows 50M After time tier 1.7M Rows scanned 18.4K Rows returned 5K
Estimated latency 42 ms Observed path
Rows scanned 18.4K 0.04% of table
Rows returned 5K 1.2 MB payload
Plan risk Low Bounded, indexed, and budgeted
Request: dashboard rollup

The query asks for a bounded dashboard trend, so a summary tier can be valid if freshness and quality fields are preserved.


      
Technical accuracy notes
Estimator boundary

This workbench is a teaching model. Real optimizers depend on statistics, storage layout, distribution, query language, hardware, concurrency, and version-specific behavior.

Time predicates

Time pruning helps only when the query uses the same time axis used for partitioning, chunking, or block ordering. Functions wrapped around the time column can prevent useful pruning.

Index shape

An index reduces candidate rows when predicates match its useful column order. More indexes can also increase write cost and storage, so they need workload evidence.

LIMIT caveat

A small result limit is not enough if the database must scan or sort a large set before it can return the first page.

Rollup and cache

Rollups and caches change the data tier. They must expose freshness, sample counts, min/max values, gap flags, or other quality evidence that the user needs.

No universal winner

InfluxDB-style, TimescaleDB-style, document, wide-column, and relational stores fit different query mixes. Validate the schema, data volume, and read pattern you will actually run.

Formula trace