Lookup Tables and FillMissing

I was wondering if you were able to use the 'fillmissing values' operator with values from a lookup table? 
for example: if i had a log search that returned 10 logs for 'x' and 0 logs for 'y', if 'x' and 'y' were both stored in a lookup table, would i be able to use the table to still display 'y' in my aggregates even though there currently isnt any logs that contain it? 

currently, i have to search for the logs and manually populate the values for the 'fillmissing' operator and it would be much more elegant if a lookup table could handle this for me.