Add test to compare distinct counts between tables

[jeffwhite-indeed]

Can we consider a test that would check that all distinct source records are present on a target table? This could confirm that our warehouse isn't missing any ids. I would imagine it might be similar to the expect_table_row_count_to_equal_other_table test, but with a distinct allowed?

[clausherther]

This could in theory be accomplished today using the base equal_expression macro, and we can easily wrap this in a more specific "expectation".

  - name: my_model_1
    tests:
        - dbt_expectations.equal_expression:
            expression: count(distinct col1)
            compare_model: ref("my_model_2")
            compare_expression: count(distinct col2)

[jeffwhite-indeed]

This could in theory be accomplished today using the base equal_expression macro, and we can easily wrap this in a more specific "expectation".

  - name: my_model_1
    tests:
        - dbt_expectations.equal_expression:
            expression: count(distinct col1)
            compare_model: ref("my_model_2")
            compare_expression: count(distinct col2)

Ha. Correct. I missed this macro as I was only reviewing the ones in the README. Cheers!