Re: Should I replace all CHAIN, SETLL, and READs to SQL

But in return for that 100 millionth of seconds of performance you are
hardwiring the physical view of the table into the program. You have lost
your database independence for a few 100 millionth of second performance
and as I have said over and over the whole performance thing starts going
out the window when you begin to consider multiple tables. Using RLA, you
chain this one and then that one and then this one. In SQL you are almost
always bringing fields from multiple tables and all your performance
measurement go out the window.


On Fri, Nov 2, 2012 at 12:40 PM, Nathan Andelin <nandelin@xxxxxxxxx> wrote:

Did you benchmark SELECT COUNT(*) FROM XXXX WHERE..... ?

Yes, select count(*) into :found ... consumes a little bit more CPU than
select 1 into :found ...

The nice thing about select count(*) is that if a record is NOT found,
then "found" contains 0, whereas select 1 into :found always places 1 in
found.

Again, if you want best performance, use SETLL to check for existence.

-Nathan

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