Information Type

Retrieved From

Singular tests

C. .sql files

Column data types

A. Data platform information schema

Generic tests

B. .yml configuration

SQL code

C. .sql files

Column descriptions

B. .yml configuration

Model dependencies

C. .sql files

The dbt docs command compiles metadata about your project by gathering information from three primary sources: your warehouse’s information schema, your YAML configuration files, and your SQL model files. Understanding which metadata comes from which source is essential for debugging and for effective documentation practices.

Singular tests live inside .sql files within the /tests directory. Since dbt renders these tests directly from SQL files, their definitions appear in documentation sourced from that location.

Column data types come from the warehouse itself. dbt introspects the data platform information schema to retrieve actual types because dbt does not infer or define column types—only the warehouse does.

Generic tests (e.g., unique, not_null, accepted_values) are declared in .yml files. These YAML definitions contain test configurations, descriptions, and parameters, which dbt uses to document and execute these tests.

SQL code for models is naturally sourced from .sql files where the models are defined. This includes logic such as SELECT statements, CTEs, and transformations.

Column descriptions are written exclusively in .yml files. dbt never extracts descriptions from SQL comments—only from YAML.

Model dependencies come from the ref() and source() calls inside .sql model files, which dbt parses to build the DAG.