diff --git a/.changes/unreleased/Features-20240715-205845.yaml b/.changes/unreleased/Features-20240715-205845.yaml
new file mode 100644
index 00000000..3bdb6ef1
--- /dev/null
+++ b/.changes/unreleased/Features-20240715-205845.yaml
@@ -0,0 +1,6 @@
+kind: Features
+body: Added macro to allow adapter-specific choice of unspecified value in unit tests
+time: 2024-07-15T20:58:45.587529+02:00
+custom:
+    Author: steffen030
+    Issue: "10447"
diff --git a/dbt/include/global_project/macros/relations/column/columns_spec_ddl.sql b/dbt/include/global_project/macros/relations/column/columns_spec_ddl.sql
index 7a56d09e..0faf9d0b 100644
--- a/dbt/include/global_project/macros/relations/column/columns_spec_ddl.sql
+++ b/dbt/include/global_project/macros/relations/column/columns_spec_ddl.sql
@@ -87,3 +87,11 @@
   {% set formatted = column.column.lower() ~ " " ~ data_type %}
   {{ return({'name': column.name, 'data_type': data_type, 'formatted': formatted}) }}
 {%- endmacro -%}
+
+{% macro render_unspecified_column_value(column_type) %}
+  {{ return(adapter.dispatch('render_unspecified_column_value', 'dbt') (column_type)) }}
+{% endmacro %}
+
+{% macro default__render_unspecified_column_value(column_type) %}
+    safe_cast('null', {{column_type}})
+{% endmacro %}
diff --git a/dbt/include/global_project/macros/unit_test_sql/get_fixture_sql.sql b/dbt/include/global_project/macros/unit_test_sql/get_fixture_sql.sql
index a3a8173b..ab103f84 100644
--- a/dbt/include/global_project/macros/unit_test_sql/get_fixture_sql.sql
+++ b/dbt/include/global_project/macros/unit_test_sql/get_fixture_sql.sql
@@ -19,7 +19,7 @@
 {%- endif -%}
 
 {%- for column_name, column_type in column_name_to_data_types.items() -%}
-    {%- do default_row.update({column_name: (safe_cast("null", column_type) | trim )}) -%}
+    {%- do default_row.update({column_name: (render_unspecified_column_value(column_type) | trim )}) -%}
 {%- endfor -%}
 
 {{ validate_fixture_rows(rows, row_number) }}