> No, FB just now can't use the same index to join/filter and to sort.
> But in some conditions this can FB clone Yaffil. Work on merging codes
> should start just after FB1.5 release.

I'm not sure I understand. You say that FB can't use the same index both to join/filter and to sort...

But in a book I have (the only one in Czech, written by Pavel Cisar) - if i remenber it correctly - there's a statement that if FB reports in the query plan that it's going to ORDER the rows using index, one can't tell whether it's going also to FILTER using the index or not. This sentence would imply that it IS possible and that it happens. I'll take one more look into the book, but the opposite wouldn't make any sense for me since it's trivial to use the ORDERED-employed index also to filter rows.

>
> BTW, FB don't accept explicit plans like
>
> Plan(
> Table1 Order Index1, /*to sort*/
> Table1 Index (Index2) /*to join or filter*/
> ...
> )
>
> but this is only syntax limitation, in fact optimizer often builds
> such a plans itself but when reporting plan shows only usage index for
> sort :) To check this Dan can create separate index (say, New_Index)
> on Action_Time and make

Yes, I'm aware of these limitations. Is it going to change in sometime in the future?

Jakub
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