D
Dmitri Levin
Guest
The existence of primary index in OE is the result of the absence of cost based optimization. Some index has to be chosen for any 4GL query. Even if the table does not have an index at all, it will still have a designated "default" index that will be chosen for all queries. I believe it will be index based on recid. For good written 4GL code it does not matter what index is Primary, because the choice should not come to number 7) in the quote above that George provided. On a decent modern hardware with SSDs and huge memory available now last thing to worry is about the data physically stored in some index order. So the primary index choice boils down to what sorting order is most logically natural for the query without a WHERE condition. FOR EACH table-name NO_LOCK:
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