diff --git a/pkgs/standards/autoapi/autoapi/v3/ddl/__init__.py b/pkgs/standards/autoapi/autoapi/v3/ddl/__init__.py
index fc0bd6a9bb..d5ce5b271b 100644
--- a/pkgs/standards/autoapi/autoapi/v3/ddl/__init__.py
+++ b/pkgs/standards/autoapi/autoapi/v3/ddl/__init__.py
@@ -209,12 +209,29 @@ def _create_all_on_bind(
             attachments = sqlite_default_attach_map(engine, schema_names)
 
     if attachments:
-        bootstrap_dbschema(
+        info = bootstrap_dbschema(
             engine,
             schemas=schema_names,
             sqlite_attachments=attachments,
             immediate=True,
         )
+        # If schemas were collected, treat the DSN path as a base path by
+        # removing the original SQLite file once schema-specific attachments
+        # have been created. This avoids leaving behind an unused ``main``
+        # database like ``authn.db`` alongside the expected
+        # ``authn__authn.db`` attachment.
+        if getattr(engine.dialect, "name", "") == "sqlite":
+            base_db = getattr(getattr(engine, "url", None), "database", None)
+            if base_db and base_db not in (":memory:", ""):
+                base_path = Path(base_db)
+                attached_paths = {
+                    Path(p) for p in info.get("sqlite_attachments", {}).values()
+                }
+                if base_path.exists() and base_path not in attached_paths:
+                    try:
+                        base_path.unlink()
+                    except OSError:
+                        pass
     else:
         ensure_schemas(engine, schema_names)
 
diff --git a/pkgs/standards/autoapi/tests/unit/test_sqlite_attachments.py b/pkgs/standards/autoapi/tests/unit/test_sqlite_attachments.py
index 64af776267..7ce2a05c7f 100644
--- a/pkgs/standards/autoapi/tests/unit/test_sqlite_attachments.py
+++ b/pkgs/standards/autoapi/tests/unit/test_sqlite_attachments.py
@@ -1,5 +1,8 @@
 import pytest
 from autoapi.v3.autoapp import AutoApp
+from autoapi.v3.orm.tables import Base
+from autoapi.v3.orm.mixins import GUIDPk
+from autoapi.v3.types import Column, String
 
 
 def _db_names(conn):
@@ -47,3 +50,22 @@ async def test_initialize_async_with_sqlite_attachments(async_db_session, tmp_pa
         result = await conn.exec_driver_sql("PRAGMA database_list")
         names = {row[1] for row in result.fetchall()}
     assert "logs" in names
+
+
+@pytest.mark.asyncio
+async def test_dsn_treated_as_base_path(tmp_path):
+    """Ensure only schema-attached SQLite database files are created."""
+    base = tmp_path / "authn.db"
+
+    class Model(Base, GUIDPk):
+        __tablename__ = "things"
+        __table_args__ = {"schema": "authn"}
+        name = Column(String, nullable=False)
+
+    api = AutoApp(engine=f"sqlite+aiosqlite:///{base}")
+    api.include_model(Model)
+    await api.initialize()
+
+    attach_path = tmp_path / "authn__authn.db"
+    assert attach_path.exists()
+    assert not base.exists()