[feat] add not_null_multiple_columns test

tests/generic/not_null_proportion_multiple_columns.sql

@@ -0,0 +1,46 @@
+{% test not_null_proportion_multiple_columns(model, threshold=0.99) %}
+
+    {%- set columns = adapter.get_columns_in_relation(model) -%}
+    {% set suffix = '_nulls' %}
+    {% set pivot_columns_query %}
+
+        with null_counts as(
+
+            select 
+                {% for column in columns -%}
+                SUM(CASE WHEN {{ column.name }} IS NULL THEN 1 ELSE 0 END) AS {{ column.name }}{{ suffix }},
+                {%- endfor %}
+                count(*) as total_records
+                from {{ model }}        
+        ),
+
+        pivot_columns as (
+
+            {% for column in columns -%}
+            select '{{ column.name }}' as column_name, {{ column.name }}{{ suffix }} as quantity, total_records
+            from null_counts
+            {% if not loop.last %}union all {% endif %}
+            {%- endfor %}
+        ),
+
+        faulty_columns as (
+            select
+                *
+            from pivot_columns
+            where
+                quantity / total_records > (1 - {{ threshold }})
+
+
+        )
+        select * from faulty_columns
+    {% endset %}
+    with validation_errors as (
+    {%- set errors = dbt_utils.get_query_results_as_dict(pivot_columns_query) -%}
+    {% for e in errors['column_name'] | unique %}
+        {{ log("LOG: Coluna com porcentagem de não nulos menor que " ~ threshold * 100 ~ "% ---> " ~ e ~ "  [FAIL]", info = True) }}
+        select '{{e}}' as column
+        {% if not loop.last %}union all {% endif %}
+    {% endfor %})
+
+    select * from validation_errors
+{% endtest %}