[V4RB] Best way to implement Uniqueness Across 2 Fields

[Bob Keeney]

I have a table that has 2 fields, a string and a ptr to another table.

sWord, vstring
ptrCase, vPtrObject

What is the best way to implement a unique record based on sWord and 
ptrCase?  For example, the values (Dog, 1) and (Dog, 2) are valid but I 
don't want the user to add another (Dog, 1).  Am I going to have to do 
this via code?  Will I have to do a SQL check before attempting to add 
the value?

I need this to be as fast as possible because this table could be 
500,000+ rows.  Any help is appreciated.

Thanks,
Bob Keeney