> -----Ursprüngliche Nachricht-----
> Von: joseigd [mailto:joseigd@...]
> Gesendet: Donnerstag, 9. Dezember 2004 12:24
> An: firebird-support@yahoogroups.com
> Betreff: [firebird-support] "Key size too big" with 80 characters?
>
>
>
>
> Hi all,
>
> In a FB 1.5 database, I have a table with two VARCHAR fields,
> of 60 and 20 characters respectively.
>
> I tried to create an index for these two fields and got the
> infamous message "key size too big for index ... ".
>
> I'm using WIN1252 and PXW_SPAN. The IB 6 docs say that
> WIN1252 uses 1 byte for each character (don't know whether
> the collation order adds to the storage requirement for the index).
>
> In another posts in this list, some users reported this error
> with Unicode for example, and they were trying to index
> fields of more than 100 characters. I cannot understand why
> WIN1252 + PXW_SPAN require more bytes than the Unicode character set.
>
> TIA for your help
>
> --
> José
>

Maybe this will help you a little bit:
http://www.volny.cz/iprenosil/interbase/ip_ib_indexcalculator.htm

Regards, Alex