I'm attempting to locate some documentation on Derived Tables and how indexes work with them, any caveats, anything special that needs to be done. I am finding nothing on the web nor in the ASE manuals nor ASE Books covering the developer, admin, performance & tuning realms.
The issue I'm having is with code that is using Derived Table joins and I can't seem to locate why it's not choosing the correct index. I've added a column to 1 of the nonclustered indexes. I'm assuming the optimizer would choose the underlying table's index but that doesn't seem to be the case here.
Any help would be most appreciated!!
Thank you and Best Regards,