analytics-dictionary / term / transformation & metrics

Surrogate key

A surrogate key is a generated identifier, with no business meaning, used to uniquely identify a row in a table.

Written by Reflective Data experts · updated Oct 5, 2026

It protects models from changes in source identifiers and makes joins simpler and more reliable, especially when natural keys combine several columns. Often generated by hashing the natural key columns.

Consistent key generation is important for incremental models and tests.

Data modeling dbt Star schema

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Metric

A metric is a quantitative measure of performance, such as revenue, conversion rate or active users.

analytics-engineering.md

Analytics engineering

Analytics engineering is applying software engineering practices to analytics: version control, testing, documentation and modular code.

dbt-snapshot.md

dbt snapshot

A dbt snapshot records changes to a mutable table over time, producing a history of each…

lookml.md

LookML

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

data-mart.md

Data mart

A data mart is a focused subset of a warehouse built for one team or subject,…

dbt-macro.md

dbt macro

A dbt macro is a reusable piece of SQL logic written with Jinja templating.

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