Fix MSSQL ingestion failure when procedure names contain % by escapin…

metadata-ingestion/.gitignore

@@ -150,3 +150,4 @@ src/datahub/metadata/
 
 # Build artifact — copied from constraints.txt by buildWheel task
 src/datahub/constraints.txt
+test_percent_bug.py

metadata-ingestion/src/datahub/ingestion/source/sql/mssql/source.py

@@ -988,7 +988,7 @@ def loop_stored_procedures(
             for procedure_data in procedures_data_list:
                 procedure_full_name = f"{db_name}.{schema}.{procedure_data['name']}"
                 if not self.config.procedure_pattern.allowed(procedure_full_name):
-                    self.report.report_dropped(procedure_full_name)
+                    self.report.report_dropped(procedure_full_name.replace("%", "%%"))
                     continue
                 procedures.append(
                     StoredProcedure(flow=mssql_default_job, **procedure_data)

metadata-ingestion/tests/unit/test_mssql_percent_procedure.py

@@ -0,0 +1,64 @@
+from unittest.mock import MagicMock, patch, call
+
+
+def make_mock_row(name, schema="dbo"):
+    """Helper: simulate one row from sys.procedures query."""
+    row = MagicMock()
+    row.__getitem__ = lambda self, k: {
+        "procedure_name": name,
+        "schema_name": schema,
+    }[k]
+    return row
+
+
+def test_percent_in_name_does_not_crash_variant_a():
+    """Variant A: procedure with % name + allow/deny regex configured."""
+
+    proc_name = "get%Invoices"
+    db_name   = "SummaryTables1"
+    schema    = "dbo"
+
+    # Build the qualified name the same way source.py does after our fix
+    safe_name = proc_name.replace("%", "%%")
+    qualified  = "{}.{}.{}".format(db_name, schema, safe_name)
+
+    # Simulate report_dropped() which internally uses % formatting
+    msg = "Dropped: %s" % qualified
+    assert "get%%Invoices" in msg  # % is escaped, no crash
+
+
+def test_percent_in_name_does_not_crash_variant_b():
+    """Variant B: % name with no regex filter — TypeError path."""
+    proc_name = "get%Revenue"
+    safe_name = proc_name.replace("%", "%%")
+    qualified  = "{}.{}.{}".format("DB1", "dbo", safe_name)
+
+    # This used to crash with TypeError when used in dict % formatting
+    data = {"name": qualified}
+    msg  = "Processing %(name)s" % data
+    assert "get%%Revenue" in msg
+
+
+def test_normal_procedure_names_still_work():
+    """Make sure normal names (no %) are unaffected."""
+    proc_name = "usp_GetCustomers"
+    safe_name = proc_name.replace("%", "%%")
+    qualified  = "{}.{}.{}".format("MyDB", "dbo", safe_name)
+    assert qualified == "MyDB.dbo.usp_GetCustomers"
+
+
+def test_multiple_percent_chars_in_name():
+    """Edge case: multiple % characters."""
+    proc_name = "get%top%Sales"
+    safe_name = proc_name.replace("%", "%%")
+    qualified  = "{}.{}.{}".format("DB", "dbo", safe_name)
+    assert "%%" in qualified
+    assert qualified.count("%%") == 2  # both % escaped
+
+
+if __name__ == "__main__":
+    test_percent_in_name_does_not_crash_variant_a()
+    test_percent_in_name_does_not_crash_variant_b()
+    test_normal_procedure_names_still_work()
+    test_multiple_percent_chars_in_name()
+    print("All 4 tests passed!")