I did that and didn't work, this is my code:

lcAlias = SYS(2015)

SET ANSI ON
&lcSQL into cursor &lcAlias

IF RECCOUNT(lcAlias) > 0 THEN
lcFieldName = FIELD(1, lcAlias)

lcFieldName = lcAlias + "." + lcFieldName
lRetVal = &lcFieldName
ELSE
lRetVal = NULL
ENDIF

The other problem, I am havin is that if I run a query in FoxPro or intantiate the class in foxpro I get the value the query should return, but If I instantiate it from the dll, and the sql command with the code above, I get a value that has nothing to do with the value. at the beginning I was thinking it was getting the value from other table, that is why i explicitly use alias.field, but still doesn't work.