Re: RPG SQL and Cursors

Aaron

Set operations include updates and deletes. Yes, they can be done in embedded SQL with a cursor or with RLA. If done with an UPDATE ... WHERE statement, yes, somewhere the database will go through the several records. But we hope that the DB system can do it more efficiently. Codewise, it's certainly simpler - and EXECUTE IMMEDIATE in some cases, PREPARE and USING in others.

Of course, a DOW with a keyed DELETE is pretty simple code, too!

Vern

On 11/18/2010 3:18 PM, Aaron Bartell wrote:

Now you have me curious. What do you do with a set of records as a whole
vs. process them row by row? It would seem to me that at some point a row
needs to be processed by iteself.

Aaron Bartell
www.MowYourLawn.com/blog
www.OpenRPGUI.com
www.SoftwareSavesLives.com



On Thu, Nov 18, 2010 at 2:23 PM, Charles Wilt<charles.wilt@xxxxxxxxx>wrote:

Surprisingly, nobody's thrown my name out here yet...but "if you're
using a cursor you're probably doing something wrong" is definitely a
phrase I've thrown out here many times.

The point being SQL is designed for sets or records, but to many
people do things row by row since that what they are used to.

It's not just our platform, happens on other too. One of the MS SQL
Server guru's coined the term RBAR - Row By Agonizing Row....pherhaps
I'll steal it :)

Sometimes cursors are the right or the only way to do something...but
too often they are a poor choice.

In any event, like Scott, I'm confused as to what you're asking.
SQL-CLI doesn't really factor into the use or non-use of cursors.

What do you want to do?

Charles

On Thu, Nov 18, 2010 at 12:34 PM, Jeff Young<cooljeff913@xxxxxxxxx>
wrote:

I have seen it indicated in many posts in the past that if you are using

cursors

in SQL, you are doing something wrong.
If I have only RPGLE and CL to work with and SQL-CLI is not an option,

how would

I select multiple rows for a set of conditions and return them in an

ordered

condition using embedded SQL with a CURSOR?

Thanks,

Jeff Young
Sr. Programmer Analyst
IBM -e(logo) server Certified Systems Exper - iSeries Technical Solutions

V5R2

IBM Certified Specialist- e(logo) server i5Series Technical Solutions
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