AW: Various silliness in heap_getnext and related routi nes - Mailing list pgsql-hackers

From Zeugswetter Andreas SB
Subject AW: Various silliness in heap_getnext and related routi nes
Date
Msg-id 11C1E6749A55D411A9670001FA68796336831A@sdexcsrv1.f000.d0188.sd.spardat.at
Whole thread Raw
List pgsql-hackers
> These pointers are useless
> except in the very unusual case where one steps forward and then back
> in a sequential scan (for example, "FETCH 1; FETCH BACKWARD 1;" in a
> cursor).

Actually I think it should be known whether a fetch backward is actually
allowed for a particular cursor, since it usually needs to be declared 
as a scroll cursor explicitly. 

>  It seems to me that this is wrongheaded.  We could simplify
> and speed up the normal case by maintaining only a "current" pointer,
> which would be well worth the extra work in the forward/back 
> step case.

So it probably does pay off for a cursor, that is explicitly requested 
to be scrollable, but certainly not for others, yes.

Andreas


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