>>>I just found to my surprise, that EMPTY() is NOT a Rushmore optimized function. Why is this? I would think this would definitely be supported.. Anyways, is there a faster/cleaner/better way to do the same thing in my Rushmore optimizable expressions other than FIELD=SPACE(8) or FIELD != SPACE(8)? ISNULL() only works if you set your DBF files up with a null value, I believe-- and I need to retain backwards compatibility with other DBF files. Thanks for any help.
>>
>>

---

field == ""
>
>'==' means exactly equal-- equal in character length. A character field with 1-255 characters will never be exactly equal to a zero-length character string. I could use FIELD == ' ' with the neccessary spaces inside, but that's extra work to find out the size of each field I need to evaluate. FIELD=" " would work better, but if the character expression starts with a space, that would cause a problem. I was looking more for a universal function that could be used(at least for strings-- preferrably numeric as well) that was Rushmore Optimizeable-- just to evaluate if the FIELD was empty(the FIELD **always** has a length, however).

---

Yes Derek,
It means exactly equal, and both sides are "padded to same size" before comparison. That's if your char field is n length, right side would be space(n). A Rushmore optimizable empty(field). !(field == "") would correspond to !empty(field). Just try it with any table :

select * from mytable where myCharField = ""

select * from mytable where myCharField == ""

return different sets where latter returns the records that empty(myCharField).
field == "" is Rushmore optimizable but not !field == ""

select * from myTable ;
  where pkfield not in ;
  (select pkfield from myTable where myField == "")

is Rushmore optimized version of !empty(). But of course for the latter you might want to use a shorter Rushmore optimized one :

select * from myTable where myField # space(fsize("myField","myTable"))

Also there is another option that might be the choice in this situation and fully Rushmore optimizable :

set ansi on
select * from myTable where myField = "" && empty(field)
select * from myTable where myField != "" && !empty(field)

("set ansi" effects SQL not "set exact").
Cetin