>Hi every body
>
>Whether is there any difference in the speed of data access between the following two methods in relational tables?
>
>1) Setting relation on a common numeric field
>2) Setting relation on a compound of two character fields
>
>I am using VFP 6
>
>Thank you very much,
>Ali

In practice almost no. In theory (and might turn out to be practice in huge tables) as the size of key increases, access to index node would be slower. Think like this :
You have a series of cars and vagons. The key position is 3rd. It'd still be faster to move to 3rd car than to 3rd vagon.
PS: Honestly AFAIK index structure is not as simple as this sample just for a rough idea.
Check bintoc(). It's recommended to produce smaller index key sizes when applicable.
Cetin