How works $__name in prefix/postfix

Hi all,

I’m trying to insert $__name value into prefix/postfix field, but doesn’t works for me.
I’m using grafana 5.4.0 over MS SQL, my query for singlestat is:

  • select val as value, ‘prefix’ as metric from tablename

I also tryed to change the metric column alias to name, but doesn’t work too.

This is the result:

I don’t known if I must use other column alias for assign value to __name, in that case, can anyone say me what is the correct column alias to be used for assign its value to __name.

Thanks in advance