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. It can also include any arguments or configurations passed to those tests.
Once these tests are defined, you can validate their correctness by running
This test validates that there are no
null values present in a column.
version: 2models:- name: orderscolumns:- name: order_idtests:- not_null
This test validates that there are no duplicate values present in a field.
version: 2models:- name: orderscolumns:- name: order_idtests:- unique
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.
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
version: 2models:- name: orderscolumns:- name: statustests:- accepted_values:values: ['placed', 'shipped', 'completed', 'returned']- name: status_idtests:- accepted_values:values: [1, 2, 3, 4]quote: false
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
version: 2models:- name: orderscolumns:- name: customer_idtests:- relationships:to: ref('customers')field: id
to argument accepts a Relation – this means you can pass it a
ref to a model (e.g.
ref('customers')), or a
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:
version: 2models:- name: orderstests:- unique:column_name: "country_code || '-' || order_id"
Define and use a custom generic test
If you define your own custom generic ("schema") test, you can use that as the
version: 2models:- name: orderscolumns:- name: order_idtests:- primary_key
Check out the guide on writing a custom generic test for more information.