analytics-dictionary / tool overview / transformation & metrics

LookML

LookML is the modelling language of Looker, used to define data models, dimensions and measures.

Written by Reflective Data experts · updated Oct 5, 2026

Developers describe views, joins and metrics in LookML files stored in git, and Looker uses them to generate SQL for any exploration or dashboard.

It is a mature semantic layer, tightly coupled to Looker.

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A metric tree breaks a top-level metric down into the input metrics that drive it.

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