Re: SQLRPGLE - scrollable cursor, set at a specific record

"RPG400-L" <rpg400-l-bounces@xxxxxxxxxxxx> wrote on 08/09/2016 10:26:12
AM:

For me, I find it better to use an expanding subfile, and do repeated

reads

to manually find the value if a position-to is required. This way, a
scrollable cursor is not needed. I have one application with a

scrollable

cursor, and I didn't find a lot of advantage to it.

An expanding subfile is good up to 9,999 rows (the limit of a
subfile). Some would say that if the user wants to scroll beyond that
then they should be forced to put in a key value from which to re-start.
But, imagine the performance drain if you had to programmatically search a
9,999 row subfile only to find that the requested key value is not in the
subfile and you then have to open a new cursor anyway? Now, it is
possible to do a binary search of the subfile and alleviate that problem.
;-)

That said, the use I find for a scrollable cursor is if you decide
that your subfile is never more than one page in size and a position-to
request is always satisfied by closing and reopening the cursor starting
at the new position.

Sincerely,

Dave Clark