Atlas · skill

dbt

dbt organizes data transformations as versioned projects with declared dependencies, tests and documentation. The skill uses those projects to build dependable analytical models in a supported data platform, making transformation logic reviewable and connecting source tables to the datasets consumed by analysts and AI pipelines.

toolTransformation

What it is

A dbt model expresses a transformation that produces a relation or other supported output in the target platform. References between models form a dependency graph, allowing dbt to determine execution order and generate lineage information. Materialization choices determine whether results are stored as tables, views or incremental structures. Tests express expectations about the produced data, while documentation records meaning and ownership. dbt focuses on transformation rather than serving as a universal extraction engine or replacing the warehouse. Competence therefore includes SQL and data-model semantics as well as project configuration and an understanding of how the destination executes the generated work.

What the work involves

The practitioner defines sources and models, uses explicit references and selects materializations appropriate to update patterns. They add tests for keys, relationships and important business assumptions, then review generated queries and warehouse behavior. Useful artifacts include a documented transformation graph and an incremental model's recovery strategy. CI should evaluate changed models with representative data where feasible. The team also checks full refreshes, late corrections and deletion handling, because an incremental query that works on a new batch may still produce incorrect historical results.

Illustrative example

A revenue model combines order lines, discounts and refunds. The dbt project separates cleaned sources from business aggregates and tests that order-line identifiers are unique. A new refund rule changes the historical transformation, so the engineer plans a backfill rather than assuming an incremental run will repair earlier totals. Documentation explains the metric's grain and treatment of canceled orders, allowing analysts to interpret the resulting table correctly.

Limits and common mistakes

Tests can miss semantic errors, and a well-organized graph can still encode incorrect joins or metric definitions. Incremental models add assumptions about change detection and recovery that need explicit validation. Destination-specific behavior also affects performance and correctness. dbt does not remove the need for source quality, orchestration or access governance. The strongest projects keep model meaning understandable and demonstrate how changes affect both current and historical outputs.

Prerequisites

  • hardSQL

    dbt IS SQL with Jinja templating — SQL proficiency is the absolute prerequisite

Related skills

  • → is an instance of: Data Engineering

Sources and further reading

Last updated: 2026-10-10