i use
my steps
1. create a new database ckdb on mysql, then  create table t1(a int, primary key(a)); and insert some rows
2. SET allow_experimental_database_materialize_mysql=1; at clickhouse, 
3. CREATE DATABASE ckdb ENGINE = MaterializeMySQL('127.0.0.1:3306', 'ckdb', 'root', 'A123b_456');
4. use ckdb and select * from t1 ok
5. create table dzm as select * from others in mysql ----> cannot see dzm in clickhouse, but if select * from t1, reports
```
Code: 48. DB::Exception: Received from localhost:9000. DB::Exception: The ckdb.dzm cannot be materialized, because there is no primary keys..
```
6. create table t2(a int,b int primary a);----> cannot see t2 in clickhouse, , but if select * from t1, reports
```
Code: 44. DB::Exception: Received from localhost:9000. DB::Exception: Sorting key cannot contain nullable columns.
```
<del>7. if i drop ckdb and recreate it, all tables can be selected </del>
7.if there are some 'bad' tables in a database, all tables in that database cannot be selected

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rewritten_command->rename_to = std::make_shared<ASTIdentifier>(new_column_name);
                rewritten_alter_query->command_list->add(rewritten_command);
            }
        }
        else if (alter_command->type == MySQLParser::ASTAlterCommand::RENAME_TABLE)
        {
            const auto & to_database =  resolveDatabase(alter_command->new_database_name, mysql_database, mapped_to_database, context);
            if (to_database != mapped_to_database)
                throw Exception("Cannot rename with other database for external ddl query.", ErrorCodes::NOT_IMPLEMENTED);
            
            
            if (rewritten_rename_query->elements.empty())
                rewritten_rename_query->elements.push_back(ASTRenameQuery::Element());
            rewritten_rename_query->elements.back().from.database = mapped_to_database;
            rewritten_rename_query->elements.back().from.table = alter_query.table;
            rewritten_rename_query->elements.back().to.database = mapped_to_database;
            rewritten_rename_query->elements.back().to.table = alter_command->new_table_name;
        }
    }
    ASTs rewritten_queries;
    
    if (!rewritten_alter_query->command_list->commands.empty())
        rewritten_queries.push_back(rewritten_alter_query);
    if (!rewritten_rename_query->elements.empty())
        rewritten_queries.push_back(rewritten_rename_query);
    return rewritten_queries;
}
}
}