Some followups to MATERIALIZED pg_catalog views (#8149)

Add another comment and some code to support patching the changes in
that got lost in another working directory.

Follow-up to #8145.

edb/pgsql/metaschema.py

@@ -6294,6 +6294,10 @@ def _generate_sql_information_schema(
     backend_version: params.BackendVersion
 ) -> List[dbops.Command]:
 
+    # Helper to create wrappers around materialized views.  For
+    # performance, we use MATERIALIZED VIEW for some of our SQL
+    # emulation tables. Unfortunately we can't use those directly,
+    # since we need tableoid to match the real pg_catalog table.
     def make_wrapper_view(name: str) -> trampoline.VersionedView:
         return trampoline.VersionedView(
             name=("edgedbsql", name),

edb/server/bootstrap.py

@@ -750,10 +750,19 @@ def _generate_drop_views(
     for cv in reversed(list(group)):
         dv: Any
         if isinstance(cv, dbops.CreateView):
-            dv = dbops.DropView(
+            # We try deleting both a MATERIALIZED and not materialized
+            # version, since that allows us to switch between them
+            # more easily.
+            dv = dbops.CommandGroup()
+            dv.add_command(dbops.DropView(
                 cv.view.name,
                 conditions=[dbops.ViewExists(cv.view.name)],
-            )
+            ))
+            dv.add_command(dbops.DropView(
+                cv.view.name,
+                conditions=[dbops.ViewExists(cv.view.name, materialized=True)],
+                materialized=True,
+            ))
         elif isinstance(cv, dbops.CreateFunction):
             dv = dbops.DropFunction(
                 cv.function.name,