diff --git a/tipg/collections.py b/tipg/collections.py
index 3f20adc9..e801688d 100644
--- a/tipg/collections.py
+++ b/tipg/collections.py
@@ -962,7 +962,7 @@ async def get_collection_index(  # noqa: C901
             table_id = table["schema"] + "." + table["name"]
             confid = table["schema"] + "_" + table["name"]
 
-            if table_id == "pg_temp.tipg_catalog" or table_id == "public.tipg_catalog":
+            if "tipg_catalog" in table_id:
                 continue
 
             table_conf = table_confs.get(confid, TableConfig())
diff --git a/tipg/database.py b/tipg/database.py
index 446564b4..c36fd505 100644
--- a/tipg/database.py
+++ b/tipg/database.py
@@ -1,8 +1,11 @@
 """tipg.db: database events."""
 
+import functools
+import os
 import pathlib
-from typing import List, Optional
+from typing import List, Optional, Union
 
+import boto3
 import orjson
 from buildpg import asyncpg
 
@@ -20,6 +23,26 @@
 DB_CATALOG_FILE = resources_files(__package__) / "sql" / "dbcatalog.sql"
 
 
+def get_rds_token(
+    host: Union[str, None],
+    port: Union[int, None],
+    user: Union[str, None],
+    region: Union[str, None],
+) -> str:
+    """Get RDS token for IAM auth"""
+    logger.debug(
+        f"Retrieving RDS IAM token with host: {host}, port: {port}, user: {user}, region: {region}"
+    )
+    rds_client = boto3.client("rds")
+    token = rds_client.generate_db_auth_token(
+        DBHostname=host,
+        Port=port,
+        DBUsername=user,
+        Region=region or rds_client.meta.region_name,
+    )
+    return token
+
+
 class connection_factory:
     """Connection creation."""
 
@@ -90,6 +113,11 @@ async def connect_to_db(
 
     con_init = connection_factory(schemas, user_sql_files, skip_sql_execution)
 
+    if os.environ.get("IAM_AUTH_ENABLED") == "TRUE":
+        kwargs["password"] = functools.partial(
+            get_rds_token, settings.host, settings.port, settings.user, settings.region
+        )
+
     app.state.pool = await asyncpg.create_pool_b(
         str(settings.database_url),
         min_size=settings.db_min_conn_size,
diff --git a/tipg/settings.py b/tipg/settings.py
index 5f3ad18b..c0d48c20 100644
--- a/tipg/settings.py
+++ b/tipg/settings.py
@@ -3,14 +3,13 @@
 import json
 import pathlib
 from typing import Any, Dict, List, Optional
-from urllib.parse import quote_plus
 
-import boto3
 from pydantic import (
     BaseModel,
     DirectoryPath,
     Field,
     PostgresDsn,
+    ValidationInfo,
     field_validator,
     model_validator,
 )
@@ -154,45 +153,22 @@ class PostgresSettings(BaseSettings):
 
     # https://github.com/tiangolo/full-stack-fastapi-postgresql/blob/master/%7B%7Bcookiecutter.project_slug%7D%7D/backend/app/app/core/config.py#L42
     @field_validator("database_url", mode="before")
-    def assemble_db_connection(cls, v: Optional[str], info: Any) -> Any:
-        """Validate and assemble the database connection string."""
+    def assemble_db_connection(
+        cls, v: Optional[str], info: ValidationInfo
+    ) -> PostgresDsn:
+        """Validate db url settings."""
         if isinstance(v, str):
-            return v
+            return PostgresDsn(v)
 
-        username = info.data["postgres_user"]
-        host = info.data.get("postgres_host", "")
-        port = info.data.get("postgres_port", 5432)
-        dbname = info.data.get("postgres_dbname", "")
-
-        # Determine password/token based on IAM flag
-        if info.data.get("iam_auth_enabled"):
-            region = info.data.get("aws_region")
-            if not region:
-                raise ValueError(
-                    "aws_region must be provided when IAM authentication is enabled"
-                )
-            rds_client = boto3.client("rds", region_name=region)
-            token = rds_client.generate_db_auth_token(
-                DBHostname=host,
-                Port=int(port),
-                DBUsername=username,
-                Region=region,
-            )
-            password = quote_plus(token)
-        else:
-            password = info.data["postgres_pass"]
-
-        db_url = PostgresDsn.build(
+        return PostgresDsn.build(
             scheme="postgresql",
-            username=username,
-            password=password,
-            host=host,
-            port=port,
-            path=dbname,
+            username=info.data.get("postgres_user"),
+            password=info.data.get("postgres_pass"),
+            host=info.data.get("postgres_host", ""),
+            port=info.data.get("postgres_port", 5432),
+            path=info.data.get("postgres_dbname", ""),
         )
 
-        return db_url
-
 
 class DatabaseSettings(BaseSettings):
     """TiPg Database settings."""