diff --git a/dbt_project.yml b/dbt_project.yml
index ff9164e..e46a373 100644
--- a/dbt_project.yml
+++ b/dbt_project.yml
@@ -13,6 +13,12 @@ models:
       +materialized: table
       tmp:
         +materialized: view
+
+quoting:
+  database: false
+  schema: true
+  identifier: true
+
 vars:
   github:
     issue_assignee: "{{ source('github', 'issue_assignee') }}"
diff --git a/macros/union/github_union_connections.sql b/macros/union/github_union_connections.sql
index 611f341..bb7245f 100644
--- a/macros/union/github_union_connections.sql
+++ b/macros/union/github_union_connections.sql
@@ -78,9 +78,23 @@
     {{ '-- identifier: ' ~ identifier ~ '\n' }}
 
     {% if relation is not none -%}
+        {%- set source_rel = source(single_source_name, single_table_name) -%}
+        {%- set source_cols = adapter.get_columns_in_relation(source_rel) -%}
+        {%- set ns = namespace(has_case_sensitive_cols=false) -%}
+        {%- if target.type == 'snowflake' -%}
+            {%- for col in source_cols -%}
+                {%- if col.name != col.name | upper -%}{%- set ns.has_case_sensitive_cols = true -%}{%- endif -%}
+            {%- endfor -%}
+        {%- endif -%}
         select
-            {{ dbt_utils.star(from=source(single_source_name, single_table_name)) }}
-        from {{ source(single_source_name, single_table_name) }} as source_table
+            {% if ns.has_case_sensitive_cols %}
+                {%- for col in source_cols %}
+                {{ adapter.quote(col.name) }} as {{ col.name }}{% if not loop.last %},{% endif %}
+                {% endfor %}
+            {% else %}
+                {{ dbt_utils.star(from=source_rel) }}
+            {% endif %}
+        from {{ source_rel }} as source_table
 
     {% else %}
         {{ exceptions.warn(exception_warning) if using_empty_table_warnings }}