Yes yes and no. If you execute a SSELECT on an indexed field, and don't specify NO.INDEX and do NOT refer at all to any other fields in the file, then index does NOT read the record to see if it even actually exists. It just retrieves the list of keys from the index.
If you specific a SSELECT on an indexed field and ALSO specify some other field criteria, then the select is *supposed* to use the index field FIRST to retrieve the list of keys and ONLY THEN read each record to see whether it matches the other criteria. So the "first pass" if you will should be lightning fast, but then IF your other criteria makes it traverse the majority of the file you are in for big Trouble with a "T" that rhymes with "P" that stands for "Pool". The reason you are in for trouble in this last case, is that traversing the majority of the file causes Disk Thrashing which is bad very bad very very bad. It causes this because you are forcing the system to reference the records out-of-disk-order. So it's jumping, jumping, jumping all over the disk in a helter skelter summer swelter. You want to avoid that. _______________________________________________ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
