I agree. Unless there is a logical need to go backwards, I only go backwards when deleting mv'd data from attributes. Far better than maintaining a mv pointer and branching when going forward.
Mark Johnson ----- Original Message ----- From: "Anthony Youngman" <[EMAIL PROTECTED]> To: <u2-users@listserver.u2ug.org> Sent: Monday, November 17, 2008 4:04 AM Subject: RE: [U2] SELECT-READNEXT That's odd > The other problem with counting backwards is if you've got a lot of fields. BASIC has optimisations for scanning forward through a list. I don't think it scans backwards very well. Go backwards and the result is not likely to be pretty. > > The only time I normally go backwards is when I have a habit of deleting the value I'm working on, and need to know I've processed every value. > > Cheers, > Wol > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of MAJ Programming > Sent: 15 November 2008 03:52 > To: u2-users@listserver.u2ug.org > Subject: Re: [U2] SELECT-READNEXT That's odd > > I would have to challenge the concept of putting the DCOUNT as the first > value and counting backwards. > > 99% of the time FOR..NEXT loops start at 1 and go to some end. We assume > that there's a test for surpassing the second variable at each iteration of > FOR. But is the first variable touched only once and not again. > > If it's touched for each iteration, then DCOUNT anywhere is excessive. If it > is only the first pass and only when working backwards, then it's too > awkward and the more readable code would be to assign it and not have it > derived per iteration, stepping in either direction. > > While noble and accurate, saving one variable when so many programmers have > zillions of variables anyway would amount to much savings. > > My 2 cents. > Mark Johnson > ----- Original Message ----- > From: "Edward Brown" <[EMAIL PROTECTED]> > To: <u2-users@listserver.u2ug.org> > Sent: Friday, November 14, 2008 12:05 PM > Subject: RE: [U2] SELECT-READNEXT That's odd > > > > Hey, save the variable by looping backwards - if the code in the loop > > allows it, of course... > > > > > > FOR A = DCOUNT(WORK.THINGY,VM) TO 1 STEP -1 > > code > > NEXT A > > > > -----Original Message----- > > Also for any newbies watching. Do not put DCOUNT as the second value in > > a > > FOR...NEXT Loop. Assign it once prior to the FOR statement and the loop > > will > > be faster. > > > > MAX=DCOUNT(WORK.ITEM.REC<17>,VM) > > FOR I=1 TO MAX > > > > My 2 cents > > Mark Johnson > > ----- Original Message ----- > > From: "Jef Lee" <[EMAIL PROTECTED]> > > To: <u2-users@listserver.u2ug.org> > > Sent: Friday, November 14, 2008 2:39 AM > > Subject: [U2] SELECT-READNEXT That's odd > > > > > > > One of our programmers wrote this snippet: > > > > > > FOR YY=1 TO DCOUNT(WORK.ITEM.REC<17>,VM) > > > LISTNUMBER='' > > > SQLCOMMAND='' > > > UNISTATEMENT='SELECT BPM.WORKITEMS WITH > > A1="':WORK.ITEM.REC<1>:'" > > AND > > > WITH A2="':WORK.ITEM.REC<2>:'" AND WITH A17="':WORK.ITEM.REC<17,YY>:'" > > AND > > > WITH A24#"C" AND WITH A24#"R" AND WITH A24#"F"' > > > *MY.REC<1>=UNISTATEMENT > > > CALL SR.EXECUTESQL(LISTNUMBER,UNISTATEMENT,SQLCOMMAND) > > > READNEXT DEPENDANT.ID ELSE > > > * NO ACTIVE ITEMS LEFT I NEED TO UPDATE THE STATUS OF THE > > > DEPENDANT TASK > > > CALL > > > SR.READSQL('BPM.WORKITEMS',DEP.TASK.REC,WORK.ITEM.REC<17,YY>,'') > > > DEP.TASK.REC<24>='A' > > > DEP.TASK.REC<8>=DATE() > > > DEP.TASK.REC<9>=TIME() > > > CALL > > > SR.WRITESQL('BPM.WORKITEMS',DEP.TASK.REC,WORK.ITEM.REC<17,YY>) > > > END > > > NEXT YY > > > > > > The FOR loop has 2 values to iterate, so it does 2 loops. The function > > > SR.EXECUTESQL()does the SELECT call. > > > Loop 1 returns 2 keys found. > > > Loop 2 returns 0 keys found. > > > What's odd is that the select list is empty on loop iteration 2 and > > the > > > READNEXT is populated the ID with the second key from the first > > iteration. > > > > > > I looked in the help PDFs and all I found was a reference to a > > corrected > > error > > > relating to memory not being released if the READNEXT did not exhaust > > the > > > SELECT list. > > > > > > Any thoughts? > > > > > > We have since changed our strategy to check the count returned > > instead. > > But it > > > would be nice to know that others have encountered this as well. > > > > > > Jeffrey Lee > > > Senior Analyst/Programmer > > > > > > IT Vision Australia Pty Ltd (ABN: 34 309 336 904) > > > PO Box 881, Canning Bridge WA 6153 > > > Level 3, Kirin Centre, 15 Ogilvie Road, Applecross, WA, 6153 > > > P: (08) 9315 7000 F: (08) 9315 7088 > > > W: http://www.itvision.com.au > > > ___________________________________________________________ > > > > > > NOTICE : This e-mail and any attachments are intended for the > > addressee(s) > > > only and may > > > contain confidential or privileged material. Any unauthorised review, > > use, > > > alteration, > > > disclosure or distribution of this e-mail (including any attachments) > > by > > an > > > unintended recipient > > > is prohibited. If you are not the intended recipient please contact > > the > > sender > > > as soon as > > > possible by return e-mail and then delete both messages. > > > ___________________________________________________________ > > > ------- > > > u2-users mailing list > > > u2-users@listserver.u2ug.org > > > To unsubscribe please visit http://listserver.u2ug.org/ > > ------- > > u2-users mailing list > > u2-users@listserver.u2ug.org > > To unsubscribe please visit http://listserver.u2ug.org/ > > > > -------------------------------------------------------------------------- > ----------------- > > Please remember to recycle wherever possible. > > Reduce, reuse, recycle, think do you need to print this e-mail? > > -------------------------------------------------------------------------- > ----------------- > > This e-mail and any attachment(s), is confidential and may be legally > privileged. It is intended solely for the addressee. If you are not the > addressee, dissemination, copying or use of this e-mail or any of its > content is prohibited and may be unlawful. If you are not the intended > recipient please inform the sender immediately and destroy the e-mail, any > attachment(s) and any copies. All liability for viruses is excluded to the > fullest extent permitted by law. It is your responsibility to scan or > otherwise check this email and any attachment(s). Unless otherwise stated > (i) views expressed in this message are those of the individual sender (ii) > no contract may be construed by this e-mail. Emails may be monitored and you > are taken to consent to this monitoring. > > > > Civica Services Limited, Company No. 02374268; Civica UK Limited, Company > No. 01628868 > > Both companies are registered in England and Wales and each has its > registered office at 2 Burston Road, Putney, London, SW15 6AR. > > -------------------------------------------------------------------------- > ----------------- > > ------- > > u2-users mailing list > > u2-users@listserver.u2ug.org > > To unsubscribe please visit http://listserver.u2ug.org/ > ------- > u2-users mailing list > u2-users@listserver.u2ug.org > To unsubscribe please visit http://listserver.u2ug.org/ > ------- > u2-users mailing list > u2-users@listserver.u2ug.org > To unsubscribe please visit http://listserver.u2ug.org/ ------- u2-users mailing list u2-users@listserver.u2ug.org To unsubscribe please visit http://listserver.u2ug.org/
