BUG#35550282 Handle mysql_audit schema

Starting with 8.1.0 (8.0.34), MDS stores the audit plugin configuration
in the `mysql_audit` schema. This schema already exists when the MDS
instance is created, causing the dump&load from MDS into MDS to fail
with the duplicate objects error.

As a fix, when using `util.dumpInstance()` with the `ocimds` option set
to true, the `mysql_audit` schema is automatically excluded from the
dump.

Change-Id: I1e1329e4eb1ab395b9ddbf40fb2c9495c8b29e6f

Author: Paweł Andruszkiewicz

modules/util/dump/dump_instance_options.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2022, Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2023, Oracle and/or its affiliates.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License, version 2.0,
@@ -85,6 +85,12 @@ void Dump_instance_options::on_unpacked_options() {
     }
   }
 
+  if (mds_compatibility().has_value()) {
+    // if MDS compatibility option is set, the schema name used by the OCI to
+    // store the audit plugin's configuration should not be dumped
+    filters().schemas().exclude("mysql_audit");
+  }
+
   m_filter_conflicts |= filters().schemas().error_on_conflicts();
   m_filter_conflicts |= filters().users().error_on_conflicts();
 }

unittest/scripts/auto/py_shell/scripts/util_dump_instance_norecord.py

@@ -3574,6 +3574,24 @@ def account_for_grant():
 #@<> Drop roles {VER(>=8.0.0)}
 session.run_sql("DROP ROLE IF EXISTS ?;", [ test_role ])
 
+#@<> BUG#35550282 - exclude `mysql_audit` schema if the `ocimds` option is set
+# setup
+schema_name = "mysql_audit"
+
+session.run_sql("DROP SCHEMA IF EXISTS !", [schema_name])
+session.run_sql("CREATE SCHEMA !", [schema_name])
+
+#@<> BUG#35550282 - option is not set, schema is dumped
+EXPECT_SUCCESS(None, test_output_absolute, { "ddlOnly": True, "showProgress": False })
+EXPECT_TRUE(os.path.isfile(os.path.join(test_output_absolute, encode_schema_basename(schema_name) + ".sql")))
+
+#@<> BUG#35550282 - option is set, schema is not dumped
+EXPECT_SUCCESS(None, test_output_absolute, { "ocimds": True, "compatibility": ["ignore_missing_pks"], "users": False, "ddlOnly": True, "showProgress": False })
+EXPECT_FALSE(os.path.isfile(os.path.join(test_output_absolute, encode_schema_basename(schema_name) + ".sql")))
+
+#@<> BUG#35550282 - cleanup
+session.run_sql("DROP SCHEMA !;", [schema_name])
+
 #@<> Cleanup
 drop_all_schemas()
 session.run_sql("SET GLOBAL local_infile = false;")