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index on substr(code2,1,7) tag xydg

HTH
Gerhard

>Sir, I have this line of code
>
>

>index on substr(alltrim(code2),1,7) tag xydg
>

>
>it displays this error message
>
>Error building for key index "c:\windows\temp\0001qlnd0098.cdx" tag "xydg"
>
>how to overcome this