(fix) generate_database_name macro should be case insensitive

dbt/include/duckdb/macros/adapters.sql

@@ -2,7 +2,7 @@
   {%- call statement('create_schema') -%}
     {% set sql %}
         select type from duckdb_databases()
-        where database_name='{{ relation.database }}'
+        where lower(database_name)='{{ relation.database | lower }}'
         and type='sqlite'
     {% endset %}
     {% set results = run_query(sql) %}
@@ -30,7 +30,7 @@
     select schema_name
     from system.information_schema.schemata
     {% if database is not none %}
-    where catalog_name = '{{ database }}'
+    where lower(catalog_name) = '{{ database | lower }}'
     {% endif %}
   {% endset %}
   {{ return(run_query(sql)) }}
@@ -135,7 +135,7 @@ def materialize(df, con):
       and table_schema = '{{ relation.schema }}'
       {% endif %}
       {% if relation.database %}
-      and table_catalog = '{{ relation.database }}'
+      and lower(table_catalog) = '{{ relation.database | lower }}'
       {% endif %}
       order by ordinal_position
 
@@ -157,7 +157,7 @@ def materialize(df, con):
         END as type
     from system.information_schema.tables
     where table_schema = '{{ schema_relation.schema }}'
-    and table_catalog = '{{ schema_relation.database }}'
+    and lower(table_catalog) = '{{ schema_relation.database | lower }}'
   {% endcall %}
   {{ return(load_result('list_relations_without_caching').table) }}
 {% endmacro %}

tests/functional/plugins/motherduck/fixtures.py

@@ -0,0 +1,27 @@
+#
+# Models
+#
+
+models__gen_data_macro = """
+select * from {{ ref("seed") }}
+"""
+
+#
+# Macros
+#
+
+macros__generate_database_name = """
+{% macro generate_database_name(custom_database_name=none, node=none) -%}
+    {{ target.database | trim }}_{{ var("build_env") | trim }}_{{ var("org_prefix") | trim }}
+{%- endmacro %}
+"""
+
+#
+# Seeds
+#
+
+seeds__example_seed_csv = """a,b,c
+1,2,3
+4,5,6
+7,8,9
+"""

tests/functional/plugins/motherduck/test_macros.py

@@ -0,0 +1,111 @@
+"""
+Test that the generate database name macro is case insensitive
+
+See DuckDB docs: https://duckdb.org/docs/sql/dialect/keywords_and_identifiers.html
+
+"Identifiers in DuckDB are always case-insensitive, similarly to PostgreSQL.
+However, unlike PostgreSQL (and some other major SQL implementations), DuckDB also
+treats quoted identifiers as case-insensitive."
+"""
+from urllib.parse import urlparse
+import pytest
+
+from dbt.tests.util import (
+    run_dbt,
+    check_result_nodes_by_name
+)
+from tests.functional.plugins.motherduck.fixtures import (
+    models__gen_data_macro,
+    macros__generate_database_name,
+    seeds__example_seed_csv,
+)
+
+
+@pytest.mark.skip_profile("buenavista", "file", "memory")
+class TestMacrosGenerateDatabaseName:
+    @pytest.fixture(scope="class")
+    def database_name(self, dbt_profile_target, request):
+        return urlparse(dbt_profile_target["path"]).path + "_ducky_ducky"
+
+    @pytest.fixture(autouse=True)
+    def run_dbt_scope(self, project, database_name):
+        project.run_sql(f"CREATE DATABASE IF NOT EXISTS {database_name}")
+        yield
+        project.run_sql(f"DROP DATABASE {database_name}")
+
+    @pytest.fixture(scope="class")
+    def seeds(self):
+        return {
+            "seed.csv": seeds__example_seed_csv,
+        }
+
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "model.sql": models__gen_data_macro
+        }
+
+    @pytest.fixture(scope="class")
+    def macros(self):
+        return {"db_name.sql": macros__generate_database_name}
+
+    @staticmethod
+    def gen_project_config_update(build_env, org_prefix):
+        return {
+            "config-version": 2,
+            "vars": {
+                "test": {
+                    "build_env": build_env,
+                    "org_prefix": org_prefix
+                },
+            },
+            "macro-paths": ["macros"],
+        }
+
+    @pytest.fixture(scope="class")
+    def project_config_update(self):
+        return self.gen_project_config_update("ducky", "ducky")
+
+    def test_dbname_macro(self, project):
+        # seed command
+        results = run_dbt(["seed"])
+        assert len(results) == 1
+        check_result_nodes_by_name(results, ["seed"])
+
+        for _ in range(3):
+            results = run_dbt(["run"])
+            assert len(results) == 1
+            check_result_nodes_by_name(results, ["model"])
+
+
+@pytest.mark.skip_profile("buenavista", "file", "memory")
+class TestMacrosGenerateDatabaseNameUpperCase(TestMacrosGenerateDatabaseName):
+    @pytest.fixture(scope="class")
+    def database_name(self, dbt_profile_target, request):
+        return urlparse(dbt_profile_target["path"]).path + "_ducky_ducky"
+
+    @pytest.fixture(scope="class")
+    def project_config_update(self):
+        return self.gen_project_config_update("DUCKY", "DUCKY")
+
+
+@pytest.mark.skip_profile("buenavista", "file", "memory")
+class TestMacrosGenerateDatabaseNameLowerCase(TestMacrosGenerateDatabaseName):
+    @pytest.fixture(scope="class")
+    def database_name(self, dbt_profile_target, request):
+        return urlparse(dbt_profile_target["path"]).path + "_DUCKY_DUCKY"
+
+    @pytest.fixture(scope="class")
+    def project_config_update(self):
+        return self.gen_project_config_update("ducky", "ducky")
+
+
+@pytest.mark.skip_profile("buenavista", "file", "memory")
+class TestMacrosGenerateDatabaseNameAllMixedCase(TestMacrosGenerateDatabaseName):
+    @pytest.fixture(scope="class")
+    def database_name(self, dbt_profile_target, request):
+        return urlparse(dbt_profile_target["path"]).path + "_dUcKy_DUckY"
+
+    @pytest.fixture(scope="class")
+    def project_config_update(self):
+        return self.gen_project_config_update("DuCkY", "dUcKy")