Fix BYTEA/geometry schema override issues

materializationengine/blueprints/client/api2.py

@@ -3518,7 +3518,9 @@ def get_table_schema(table):
         elif isinstance(column.type, Numeric):
             column_type = "number"
         else:
-            raise ValueError(f"Unsupported column type: {column.type}")
+            raise ValueError(
+                f"Unsupported column type for column '{column.name}': {column.type}"
+            )
 
         properties[column.name] = {"type": column_type}
         if format:
@@ -3619,6 +3621,13 @@ def get(
         schemas = {}
         for view_dict in dumped_views:
             view_name = view_dict["table_name"]
-            table = meta_db.database.get_view_table(view_name)
-            schemas[view_name] = get_table_schema(table)
+            try:
+                table = meta_db.database.get_view_table(view_name)
+                schemas[view_name] = get_table_schema(table)
+            except Exception as e:
+                # Degrade gracefully: one bad view shouldn't 500 the whole endpoint.
+                current_app.logger.warning(
+                    f"Failed to build schema for view '{view_name}': {e}"
+                )
+                schemas[view_name] = {"error": str(e)}
         return schemas, 200

materializationengine/workflows/deltalake_export.py

@@ -15,20 +15,17 @@
 import polars as pl
 import pyarrow as pa
 import shapely
+
+# Registers geoalchemy2's Geometry type with SQLAlchemy's PostGIS dialect so
+# the inspector recognizes 'geometry' columns during reflection instead of
+# warning "Did not recognize type 'geometry'".  Import for the side effect only.
+import geoalchemy2  # noqa: F401
 from celery.utils.log import get_task_logger
 from sqlalchemy import inspect, text
-from sqlalchemy.dialects.postgresql import BYTEA
-
-# Register a minimal geometry type so SQLAlchemy's inspector doesn't warn
-# "Did not recognize type 'geometry'" during reflection.  We decode WKB
-# ourselves — all SQLAlchemy needs to know is that it's binary.
-from sqlalchemy.dialects.postgresql import dialect as _pg_dialect
 from sqlalchemy.engine import Engine
 
 from materializationengine.celery_init import celery
 
-_pg_dialect.ischema_names["geometry"] = BYTEA
-
 celery_logger = get_task_logger(__name__)
 
 # Columns to drop from every Delta Lake export by default.
@@ -237,9 +234,7 @@ def _get_geometry_columns(connection_string: str, name: str) -> list[str]:
     """Return PostGIS geometry column names on *name*, in ordinal order.
 
     Detects columns via ``information_schema.columns.udt_name = 'geometry'``,
-    which works identically for tables, views, and materialized views.  This is
-    necessary because we alias the SQLAlchemy ``geometry`` type to ``BYTEA`` for
-    reflection, so the inspector cannot distinguish geometry from plain bytea.
+    which works identically for tables, views, and materialized views.
     """
     _validate_identifier(name)
     rows = _adbc_fetchall(