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Semantic layer

Semantic layer shows up across 2 courses in 1 layerof the data platform stack. Here's where it's taught, a free way to practice it, and what to learn next.

Where it's taught

∿Semantic & Metrics Layer

Why a Metrics Layer Exists

Metric drift is an org failure with a technical fix. This course makes the case for a metrics layer: the three-definitions-of-MAU war story, the headless BI thesis, what a metrics layer is NOT, and why adoption fails at month 6 rather than at install.

7 ch · 1h 28m

1 free

Measures, Metrics, Entities, Dimensions

The four primitives every metrics store is built on, made precise. Why a measure is not a metric, how entities are the join graph you already have, the ratio-metric order-of-aggregation trap, cumulative metrics and the time spine, and the metric DAG you never drew.

9 ch · 1h 53m

1 free

Related topics

↗metrics layer↗cumulative metrics↗dbt semantic layer↗entities↗headless BI↗measures↗metric drift↗metrics↗ratio metrics↗single source of truth

Start learning semantic layer free

The first chapter of every course is free to read — no account needed.

Start: Why a Metrics Layer Exists →All strata
Petascale Labs

The physics layer of data

From byte-level storage to business-grade metrics. Built with depth, not breadth.

Curriculum

Data Engineer RoadmapAll strataStorage & File FormatsIngestion & TransportOpen Table FormatsCompute EnginesOrchestration & PipelinesQuery Engines & OLAPSemantic & Metrics LayerPII & Data Governance

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All toolsParquet ViewerFreeSCD PlaygroundFreePII Masking GeneratorFree

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