per query allow reverse scan

[Former Member]

Hi

Is it possible to add a parameter to a specific query in ASE (Currently 15.5 here) in order to allow reverse index scans ?

I know about the global server option, but its hard to give to all queries this capability

Does ASE store a pointer to the previous page to the index page?

There are some specific lookup queries i do need to collect the max for the latest version of a composite key

Im planning to do some tests to check this for how much LIOs are done, Hopefully adding it soon here

Thanks

Alexandre

[former_member188958 · Accepted solution]

There isn't any way to allow just some queries to use backward scans.

Index pages have both a next page pointer and a previous page pointer, these pointers are maintained (unlike the pointers in DOL data pages).