>Dear Experts
>
>I have a table entitled TABLE2 contained three character type fields. On click event of command1, I have following codes
>
>SELECT table2
>INDEX ON ALLTRIM(mill)+ALLTRIM(bank)+ALLTRIM(branch) TO table21
>
>When I press command1, it shows following error message
>
>"Invalid key length"
>
>What is problem?
>How should I create this index?
>
>Please help

Tariq, don't use ALLTRIM() into a index key;
only with strange graph structures this can to be useful.

EXAMPLE:

mill,bank,brancH
'  AB   ','  CD  ','  E  ' => KEY:'ABCDE'
'  A   ','  BC  ','  DE  ' => KEY:'ABCDE'

Error occur because VFP evaluate the key expression for to compute the key lenght;
If this is not the max lenght case, a next key fire the error.

use:

mill+bank+branch

or ( !!!! i think you don't want this really )

mill-bank-branch

or
PADR(ALLTRIM(mill)+ALLTRIM(bank)+LTRIM(branch),millfsize+bankfsize...)