>Hi,
>Sorry to make you misunderstand. What I meant is.. something like invoice no.. INV00001, INV00002, TF100001, TF100002
Personally, I prefer to use only numbers for the primary keys. The user will not see the primary key.
You may still need numbers for the key the user sees. If you want to have the codes you mention above, you can assign the code in the form. Do it only when you save the record, and embed it in a transaction. This is to avoid skipping numbers (the user might start editing, and then cancel).
For the invoice, you can assign an expression like "INV" + SerialNumber("Invoice"), where SerialNumber is a function that does a lookup in a table of sequences.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)
