nn unique column reference Nodbc

hi,

i'm using a php script to get data from nav.
i have a message error like this : nn unique column reference

i searched and i founded that there is two cases.
1- if two of ur fields have the same caption
2- if there is many fields in your table.

for the first ,i have no fields with the same caption.
for the second when i delete some fields its works.

what i want to know if there is a way to bypass this because i can't delete fields from the table

hope anyone could help me
thanks a lot.