>Some people in FoxPro Windows 2.6 we using the binary key for their unique id to save some space. In Visual FoxPro with the integer field, most of the people are now using the integer field.

I decided that even though an integer allows 2 billion unique values (4 including neg.) that I would rather use a character value. I still have a counter file that I use to increment the counters, etc., but when I store the value as a primary key, I convert it to binary character data. This allows me to use primary keys that can grow in the future to whatever size I want. 2 billion seems like a lot, but you never know in Client Serve (s). Anyway when I designed the character data I was thinking more in terms of shorting the size to 3 or 2 bytes depending upon what the table was used for.

Another advantage of character primary keys is that you can concatenate them with other character keys which is very useful when you need to set up complex relations.

Peter