Update sqlglot/schema.py

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: georgesittas

sqlglot/schema.py

@@ -572,8 +572,21 @@ def _normalize_udf(
 
         if isinstance(udf, str):
             parsed: exp.Expression = exp.maybe_parse(udf, dialect=dialect)
-            udf = parsed if isinstance(parsed, exp.Anonymous) else parsed.this
+            # When parsing qualified UDF strings (e.g. "db.my_func()"), the root
+            # expression may be a Dot, with the Anonymous function call nested
+            # inside. Find the actual Anonymous node instead of blindly taking
+            # the left-hand side.
+            if isinstance(parsed, exp.Anonymous):
+                udf_expr = parsed
+            elif isinstance(parsed, exp.Expression):
+                udf_expr = parsed.find(exp.Anonymous)
+            else:
+                udf_expr = None
+
+            if not isinstance(udf_expr, exp.Anonymous):
+                raise SchemaError(f"Unable to parse UDF from: {udf!r}")
 
+            udf = udf_expr
         parts = self.udf_parts(udf)
 
         if normalize: