Ordinary database engine is deprecated but there is no simple mean to change database engine to Atomic for existing databases.

Possible options:
- ALTER DATABASE MODIFY ENGINE query.
- Flag that triggers migration at ClickHouse startup.

The latter should be easier to implement. 

if (!covering_drop_range.empty())
        {
            LOG_TRACE(log, "{} {}: it's covered by DROP_RANGE {}", log_msg_context, part_name, covering_drop_range);
            return true;
        }
        
        
        
        String covering_get_part_entry = get_part_set.getContainingPart(part_name);
        if (covering_get_part_entry.empty())
            return false;
        if (covering_get_part_entry != part_name)
        {
            LOG_TRACE(log, "{} {}: it's covered by GET_PART {}", log_msg_context, part_name, covering_get_part_entry);
            return true;
        }
        
        
        
        
        
        if (created_gets.contains(part_name))
        {
            
            
            
            LOG_TRACE(log, "{} {}: GET_PART for it is already created", log_msg_context, part_name);
            return true;
        }
        return false;