diff --git a/website/docs/reference/resource-configs/contract.md b/website/docs/reference/resource-configs/contract.md index fb25076b0d..18266ec672 100644 --- a/website/docs/reference/resource-configs/contract.md +++ b/website/docs/reference/resource-configs/contract.md @@ -14,6 +14,13 @@ When the `contract` configuration is enforced, dbt will ensure that your model's This is to ensure that the people querying your model downstream—both inside and outside dbt—have a predictable and consistent set of columns to use in their analyses. Even a subtle change in data type, such as from `boolean` (`true`/`false`) to `integer` (`0`/`1`), could cause queries to fail in surprising ways. +## Support + +At present, model contracts are supported for: +- SQL models (not yet Python) +- Models materialized as `table`, `view`, and `incremental` (with `on_schema_change: append_new_columns` or `on_schema_change: fail`) +- The most popular data platforms — though support and enforcement of different [constraint types](/reference/resource-properties/constraints) vary by platform + ## Data type aliasing dbt uses built-in type aliasing for the `data_type` defined in your YAML. For example, you can specify `string` in your contract, and on Postgres/Redshift, dbt will convert it to `text`. If dbt doesn't recognize the `data_type` name among its known aliases, it will pass it through as-is. This is enabled by default, but you can opt-out by setting `alias_types` to `false`. @@ -91,12 +98,6 @@ When you `dbt run` your model, _before_ dbt has materialized it as a table in th 20:53:45 > in macro assert_columns_equivalent (macros/materializations/models/table/columns_spec_ddl.sql) ``` -## Support - -At present, model contracts are supported for: -- SQL models (not yet Python) -- Models materialized as `table`, `view`, and `incremental` (with `on_schema_change: append_new_columns`) -- The most popular data platforms — though support and enforcement of different [constraint types](/reference/resource-properties/constraints) vary by platform ### Incremental models and `on_schema_change`