Skip to main content

About tests property

models/<filename>.yml
version: 2

models:
  - name: <model_name>
    tests:
      - <test_name>:
          <argument_name>: <argument_value>
          config:
            <test_config>: <config-value>

    columns:
      - name: <column_name>
        tests:
          - <test_name>
          - <test_name>:
              <argument_name>: <argument_value>
              config:
                <test_config>: <config-value>

Description​

The tests property defines assertions about a column, table, or view. The property contains a list of generic tests, referenced by name, which can include the four built-in generic tests available in dbt. For example, you can add tests that ensure a column contains no duplicates and zero null values. Any arguments or configurations passed to those tests should be nested below the test name.

Once these tests are defined, you can validate their correctness by running dbt test.

Out-of-the-box tests​

There are four generic tests that are available out of the box, for everyone using dbt.

not_null​

This test validates that there are no null values present in a column.

models/<filename>.yml
version: 2

models:
  - name: orders
    columns:
      - name: order_id
        tests:
          - not_null

unique​

This test validates that there are no duplicate values present in a field.

The config and where clause are optional.

models/<filename>.yml
version: 2

models:
  - name: orders
    columns:
      - name: order_id
        tests:
          - unique:
              config:
                where: "order_id > 21"

accepted_values​

This test validates that all of the values in a column are present in a supplied list of values. If any values other than those provided in the list are present, then the test will fail.

The accepted_values test supports an optional quote parameter which, by default, will single-quote the list of accepted values in the test query. To test non-strings (like integers or boolean values) explicitly set the quote config to false.

schema.yml
version: 2

models:
  - name: orders
    columns:
      - name: status
        tests:
          - accepted_values:
              values: ['placed', 'shipped', 'completed', 'returned']

      - name: status_id
        tests:
          - accepted_values:
              values: [1, 2, 3, 4]
              quote: false

relationships​

This test validates that all of the records in a child table have a corresponding record in a parent table. This property is referred to as "referential integrity".

The following example tests that every order's customer_id maps back to a valid customer.

schema.yml
version: 2

models:
  - name: orders
    columns:
      - name: customer_id
        tests:
          - relationships:
              to: ref('customers')
              field: id

The to argument accepts a Relation – this means you can pass it a ref to a model (e.g. ref('customers')), or a source (e.g. source('jaffle_shop', 'customers')).

Additional examples​

Testing an expression​

Some tests require multiple columns, so it doesn't make sense to nest them under the columns: key. In this case you can apply the test to the model (or source, seed or snapshot) instead:

models/orders.yml
version: 2

models:
  - name: orders
    tests:
      - unique:
          column_name: "country_code || '-' || order_id"

Define and use a custom generic test​

If you've defined your own custom generic test, you can use that as the test_name:

models/<filename>.yml
version: 2

models:
  - name: orders
    columns:
      - name: order_id
        tests:
          - primary_key  # name of my custom generic test

Check out the guide on writing a custom generic test for more information.

0
Edit this page