Understanding schema generation and customization¶

dbt uses the default macro generate_schema_name to decide where a model is built.

By default, it uses your target schema (target.schema) specified from your dbt environment or profile. Unlike dbt Core behavior, the target schema specified in the profiles.yml file must exist before you create your dbt Project in order for it to compile or execute successfully.

Typically, each developer has their own target schema, for example analytics_dev. For larger projects, you can set a custom schema to group models and specify the schema configuration key in your dbt_project.yml file. dbt appends it to the target schema (for example, <target_schema>_<custom_schema>) to keep intermediate and user-facing models separate.

--Models in `models/tasty_bytes/ will be built in the "*_staging" schema
models:
  tasty_bytes:
      +schema: staging

A model’s custom schema doesn’t replace the target schema; rather, dbt combines them to avoid collisions. For example, analytics_dev_staging. This is because if dbt ignored the target schema and only used the custom schema (in this case, staging), every developer would write to the same schema and overwrite each other.

If you want different behavior (for example, use only the custom schema, prepend user names, add environment prefixes, etc.), override generate_schema_name in /macros/ to change how the final schema name is built. For more information and examples, see Changing the way dbt generates a schema name (https://docs.getdbt.com/docs/build/custom-schemas#changing-the-way-dbt-generates-a-schema-name) in the dbt documentation.