multiple columns in rlm_sql

[petr.linke at seznam.cz]

Hi,
I have question, is it possible in virtual server config do something like 
this?

update control {
 &value1,&value2, ... ,&valueN="%{sql:SELECT value1,value2, ... ,valueN  
from some_table where ...}"
}

I know, that is no problem to do more sql queries like:
update control {
  &value1="%{sql:SELECT value1,from some_table where ...}"
  &value2="%{sql:SELECT value2,from some_table where ...}"
   ...
   &valueN="%{sql:SELECT valueN,from some_table where ...}"
}
but it is too expensive for performance, much better is to do with one sql 
select.

I looked into rlm_sql.c, and the line #462 - "for (i = 0; i < fields; i++) 
names[i] = field_info[i].name;" looks as multiple column separation.
I tried find some info in the freerarius WiKi and in the documentation, but 
 without success.

Thank you for any idea, Petr Linke