[Bug] if `data_type` is set for columns, the type should still be rendered in the html site produced by `dbt docs serve`

[jaime-spencer-oxb]

Is this a new bug in dbt-core?

• I believe this is a new bug in dbt-core
• I have searched the existing issues, and I could not find an existing issue for this bug

Current Behavior

When setting the property type for a column, dbt raises a warning CustomKeyInObjectDeprecation.
I'm guessing this is because it is expecting us to use the key data_type.

However, when using dbt docs generate, data_type results in blank column types, while type populates them correctly.

Expected Behavior

Ideally, both keys would be merged into a single one that does not trigger this warning.
I'm guessing data_type is the intended one moving forward, since that is what's used when enforcing model contracts.

Steps To Reproduce

models:
  - name: my_model
    columns:
      - name: "{{ var('timestamp_table_uuid_column') }}"
         description: "{{ doc('uuid') }}"
         type: string
         data_type: string

Relevant log output

Environment

Core:
  - installed: 1.11.2
  - latest:    1.11.2 - Up to date!

Plugins:
  - bigquery: 1.11.0 - Up to date!

Which database adapter are you using with dbt?

bigquery

Additional Context

No response

[graciegoheen]

Thanks for opening. type isn't one of our documented column properties (docs) so that's why you're getting the CustomKeyInObjectDeprecation warning.

while type populates them correctly

Is this true when you don't set anything (neither type nor data_type) as well?

models:
  - name: my_model
    columns:
      - name: "{{ var('timestamp_table_uuid_column') }}"
        description: "{{ doc('uuid') }}"

When you say "blank column types" are you referring to a json artifact? Or the html docs site?

[jaime-spencer-oxb]

Is this true when you don't set anything (neither type nor data_type) as well?

If I don't set either of those columns I don't get the warning, but the column type is also not set in the documentation.

When you say "blank column types" are you referring to a json artifact? Or the html docs site?

On the html docs site.

To sum up, I'm aware that data_type is the property required to enforce the model contract, however, it cannot be used to document the column in the html docs site.

[graciegoheen]

Got it - thanks for clarifying.

Here's a discourse post that covers this:

dbt gets the type information by querying the model when the docs are generated.

This sounds like a bug - I'm going to update the issue accordingly and move it over to the dbt-docs repo.

Looks like this might be because the logic to populate this field seems to be using the column type returned from get_columns(model):

                        ng-repeat-start="column in get_columns(model) track by column.index"
                        ng-click="toggle_column_expanded(column)"
                        class="column-row"
                        ng-class="{'column-row-selected': column.expanded}"
                        ng-style="{cursor: has_more_info(column) ? 'pointer' : 'auto'}">
                        <td>
                            <div>
                                <span class='text-dark'>{{ get_col_name(column.name) }}</span>
                            </div>
                        </td>
                        <td>
                            <span class='text-dark'>{{ column.type }}</p>

Acceptance criteria

• if data_type is set for my columns, the type should still be rendered in the html site produced by dbt docs serve

Do you think we should still get that type by querying the warehouse? Or should what you've configured for data_type be used as the source-of-truth?