Limit on multi-field indexes?

Am I correct in believing that there is a limit of seven columns in a
multi-filed index?

If so, is it possible to increase this limit (to at least eight) ?

Cheers and thanks,

Stephen.

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Stephen Davies Consulting                                            scldad@sdc.com.au
Adelaide, South Australia.                                             Voice: 61-8-82728863
Computing & Network solutions.                                     Fax: 61-8-82741015