Sort table on secondary index

[rayatholthill]

This is probably a very silly question. I've got Paradox 7. About 15 years ago I managed to display a table sorted on its secondary index, but can't remember how i did it. Can anyone help? I've tried putting...

Tbl.attach("records.db")
if isTable(Tbl) then
if not Tbl.setindex("alpha") then
errorshow()
endif
endIf

..... into the "open" event of both the form which displays the data and the menu which leads you to it, but with no effect. I'm obviously missing something.

"Records" is a name and address table with a unique membership number as the primary index. I want to display it ny last name and have a secondary index in the table "alpha" hopefully to do this.

Regards
Ray