Re: [U2] UniData 64 bit sanity check
Correct. We are working on them. Regards, Dan From: u2-users-boun...@listserver.u2ug.org [u2-users-boun...@listserver.u2ug.org] on behalf of Jeff Fitzgerald [j...@fitzlong.com] Sent: Friday, 8 February 2013 7:57 PM To: U2-Users@listserver.u2ug.org Subject: [U2] UniData 64 bit sanity check Hi all, Just want to get confirmation or a slap upside the head It looks to me like all the UDT Windows versions are 32 bit and that there isn't a 64 bit version - true? Thanks! Jeff Fitzgerald Fitzgerald & Long, Inc. www.fitzlong.com ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] UniData 64 bit sanity check
Last check there are no 64 bit builds for intel (win/Linux) Jeff Butera -- A tree falls the way it leans. Be careful which way you lean. The Lorax On Feb 8, 2013, at 9:57 PM, Jeff Fitzgerald wrote: > Hi all, > > Just want to get confirmation or a slap upside the head It looks to > me like all the UDT Windows versions are 32 bit and that there isn't a 64 > bit version - true? > > Thanks! > > Jeff Fitzgerald > Fitzgerald & Long, Inc. > > www.fitzlong.com > ___ > U2-Users mailing list > U2-Users@listserver.u2ug.org > http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
[U2] UniData 64 bit sanity check
Hi all, Just want to get confirmation or a slap upside the head It looks to me like all the UDT Windows versions are 32 bit and that there isn't a 64 bit version - true? Thanks! Jeff Fitzgerald Fitzgerald & Long, Inc. www.fitzlong.com ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] Record locks (Unidata 7.2)
I agree, though I find the LOCKED clause is needed more often than not in our particular environment. I've always used the following logic to determine which course of action to take. In this example: READU REC FROM FILE, ID THEN [do something] END ELSE [do something else] END [operate on REC] WRITE REC ON FILE, ID if there is an INPUT statement or a READU attempt on another record anywhere between the first READU and the WRITE in this program or any other that will lock the same record, then there needs to be a LOCKED clause and a loop. In my experience, leaving a user session unresponsive due to a missing LOCKED clause leads to closing the terminal emulator window or power cycling a dumb terminal. Sometimes this simply orphans the session, and the user hits the lock a 2nd time when they log back in. Not fun for the user or the support desk employee. We have a standard subroutine call for all LOCKED clauses that tells the user who has the lock so they can contact the culprit directly and leave I.T. out of the loop. -John -Original Message- From: u2-users-boun...@listserver.u2ug.org [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Woodward, Bob Sent: Thursday, February 07, 2013 3:56 PM To: U2 Users List Subject: Re: [U2] Record locks (Unidata 7.2) In an active user session where users are obtaining a lock for a length of time, you're right. There are lots of times, though, that lock intervention is not a benefit. It all depends on the need of the application and many situations where I would highly recommend using the default locking system of READU. -Original Message- From: u2-users-boun...@listserver.u2ug.org [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Wjhonson Sent: Thursday, February 07, 2013 3:41 PM To: u2-users@listserver.u2ug.org Subject: Re: [U2] Record locks (Unidata 7.2) I wouldn't however *recommend* this approach to locking as the user can never tell if their terminal is waiting on a lock, or just "hung" in some other odd manner, or perhaps processing a batch of something. So it's rather a nasty trick to play on the user, to just use READU without a LOCKED clause -Original Message- From: Woodward, Bob To: U2 Users List Sent: Thu, Feb 7, 2013 2:43 pm Subject: Re: [U2] Record locks (Unidata 7.2) You're exactly right. The only time you REALLY need the LOCKED clause if there is some need to change that approach. That was what I attempted to show in my first response. I guess I was a bit terse in that one, though. BobW -Original Message- From: u2-users-boun...@listserver.u2ug.org [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Anthonys Lists Sent: Thursday, February 07, 2013 2:21 PM To: u2-users@listserver.u2ug.org Subject: Re: [U2] Record locks (Unidata 7.2) On 07/02/2013 20:46, Jon Wells wrote: > What I'm wondering is; what can I put into the 'Xxx what to do if locked' section whereby it waits until the record lock clears, once it clears, set my own lock, read the record, alter the record, and then write the record (which would release my lock)? Somebody will correct me if I'm wrong, but I thought that was exactly what READU did! If you don't provide a LOCKED clause, READU will "hang" and wait until the lock clears, then read and lock the record. As I say, check the docu and make sure I'm right ... I've never had to bother much with locks ... Cheers, Wol > > > Thank you, > > Jon Wells > > ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] Record locks (Unidata 7.2)
On second thought this won't do either since it hasn't got an ELSE clause. ERR = '' LOOP TRY_AGAIN = 0 READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED - (Q)uit or Enter" INPUT REPLY: IF REPLY # 'Q' THEN TRY_AGAIN = 1 ELSE ABORT END ELSE STU.REC = '' UNTIL NOT(TRY_AGAIN) REPEAT STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID On 08/02/2013 20:12, Mecki Foerthmann wrote: Oh no, you don't have to add a label and you don't have to use GOTO. TRY_AGAIN = 1 LOOP WHILE TRY_AGAIN READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" SLEEP 2 END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID TRY_AGAIN = 0 END REPEAT On 08/02/2013 18:10, Woodward, Bob wrote: You should have written it something like this: TRY.AGAIN: READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" SLEEP 2 GOTO TRY.AGAIN END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END You have to add the label TRY.AGAIN: so you have a jump point then add the SLEEP command for 2 seconds and lastly the GOTO command so after the SLEEP expires, execution remains at the READU command. BobW ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] Record locks (Unidata 7.2)
Oh no, you don't have to add a label and you don't have to use GOTO. TRY_AGAIN = 1 LOOP WHILE TRY_AGAIN READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" SLEEP 2 END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID TRY_AGAIN = 0 END REPEAT On 08/02/2013 18:10, Woodward, Bob wrote: You should have written it something like this: TRY.AGAIN: READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" SLEEP 2 GOTO TRY.AGAIN END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END You have to add the label TRY.AGAIN: so you have a jump point then add the SLEEP command for 2 seconds and lastly the GOTO command so after the SLEEP expires, execution remains at the READU command. BobW ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] Record locks (Unidata 7.2)
I would also add some type of bailout logic in case the record NEVER frees up (user went home for the weekend). Obviously, you need to make the call on this on a case by case situation, but you would not want a critical process (like month end) to fail because Joe Blow left a record locked. Should you finish the other 99.% of month end or have it fail completely? Again, you need to make this call on a case by case basis for your application. MAX.TRIES = 1000 TRIES = 0 TRY.AGAIN: READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" SLEEP 2 TRIES += 1 IF (TRIES >= MAX.TRIES) THEN * track this condition somehow and move on GOTO SKIP END GOTO TRY.AGAIN END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END SKIP: John -Original Message- From: u2-users-boun...@listserver.u2ug.org [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Woodward, Bob Sent: Friday, February 08, 2013 1:10 PM To: Jon Wells; U2 Users List Subject: Re: [U2] Record locks (Unidata 7.2) You should have written it something like this: TRY.AGAIN: READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" SLEEP 2 GOTO TRY.AGAIN END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END You have to add the label TRY.AGAIN: so you have a jump point then add the SLEEP command for 2 seconds and lastly the GOTO command so after the SLEEP expires, execution remains at the READU command. BobW -Original Message- From: u2-users-boun...@listserver.u2ug.org [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Jon Wells Sent: Friday, February 08, 2013 9:57 AM To: U2 Users List Subject: Re: [U2] Record locks (Unidata 7.2) I should add that (in our test account) I switched to the READU statement along with a LOCKED clause -> READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END I locked one of the records in the list I was processing. When the program was working on that record, the CRT statement was executed, and the program moved right along processing the rest of the list; and record I had locked was not updated. Looking through the 'UniBasic Commands Reference' PDF, I found 'RECORDLOCKED (file.var, rec.id.expr)'. Perhaps this could be used within a LOOP to control things, allowing terminal input where the user can choose what to do about the record lock? I've decided to write the data to a new file, so this is no longer a big issue for me. If I had created the program using our vendor's tool kit, the generated code would have added all the appropriate gunk the system uses for record locks. The responses have been interesting as I've been looking for a chance to better understand how Unidata shops handle locks. Thank you, Jon Wells From: Tony Gravagno <3xk547...@sneakemail.com> To: u2-users@listserver.u2ug.org Sent: Friday, February 8, 2013 2:30 AM Subject: Re: [U2] Record locks (Unidata 7.2) I think people understand exactly what you're saying, but disagree. Most applications don't use the more rigorous coding for having a Locked clause that provides additional information to the user, retries, etc. That's not "wrong", it's just not necessary ... depending on the site. That said, when we used to have a lot of people in an office and a dumb terminal beeping was a recognized message to everyone, it was OK (generally) to just do the READU. These days with more alternative UIs, thick-client, thin-client, web services, mobile, etc, there's no one to hear that beep. So for modern development I would agree that you really don't want an unconditional lock hanging around, you want a Locked clause with logic to rollback the transaction and exit gracefully, perhaps with a message sent to the site admin. The penalty for Not having a Locked clause with a new UI is that the port will hang, the UI will receive a timeout (which many clients aren't prepared to process), and the DBMS port could be sitting there indefinitely with no one aware of the condition. This can cascade to multiple ports until suddenly everything grinds to a halt and GUI users around the world are unable to access the app. I believe some heads will be nodding here because I hear about this happening occasionally. T > From: Wjhonson > Then you're misunderstanding what I'm saying. > From: Kevin King > +1. Well stated. > > Woodward, Bob wrote: > > In an active user session where users are obtaining a lock for a > > length of time, you're right. There are lots of times, though, that > > lock intervention is not a benefit. It all depends on the need of the > > application and many situations where I would
Re: [U2] Record locks (Unidata 7.2)
You should have written it something like this: TRY.AGAIN: READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" SLEEP 2 GOTO TRY.AGAIN END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END You have to add the label TRY.AGAIN: so you have a jump point then add the SLEEP command for 2 seconds and lastly the GOTO command so after the SLEEP expires, execution remains at the READU command. BobW -Original Message- From: u2-users-boun...@listserver.u2ug.org [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Jon Wells Sent: Friday, February 08, 2013 9:57 AM To: U2 Users List Subject: Re: [U2] Record locks (Unidata 7.2) I should add that (in our test account) I switched to the READU statement along with a LOCKED clause -> READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END I locked one of the records in the list I was processing. When the program was working on that record, the CRT statement was executed, and the program moved right along processing the rest of the list; and record I had locked was not updated. Looking through the 'UniBasic Commands Reference' PDF, I found 'RECORDLOCKED (file.var, rec.id.expr)'. Perhaps this could be used within a LOOP to control things, allowing terminal input where the user can choose what to do about the record lock? I've decided to write the data to a new file, so this is no longer a big issue for me. If I had created the program using our vendor's tool kit, the generated code would have added all the appropriate gunk the system uses for record locks. The responses have been interesting as I've been looking for a chance to better understand how Unidata shops handle locks. Thank you, Jon Wells From: Tony Gravagno <3xk547...@sneakemail.com> To: u2-users@listserver.u2ug.org Sent: Friday, February 8, 2013 2:30 AM Subject: Re: [U2] Record locks (Unidata 7.2) I think people understand exactly what you're saying, but disagree. Most applications don't use the more rigorous coding for having a Locked clause that provides additional information to the user, retries, etc. That's not "wrong", it's just not necessary ... depending on the site. That said, when we used to have a lot of people in an office and a dumb terminal beeping was a recognized message to everyone, it was OK (generally) to just do the READU. These days with more alternative UIs, thick-client, thin-client, web services, mobile, etc, there's no one to hear that beep. So for modern development I would agree that you really don't want an unconditional lock hanging around, you want a Locked clause with logic to rollback the transaction and exit gracefully, perhaps with a message sent to the site admin. The penalty for Not having a Locked clause with a new UI is that the port will hang, the UI will receive a timeout (which many clients aren't prepared to process), and the DBMS port could be sitting there indefinitely with no one aware of the condition. This can cascade to multiple ports until suddenly everything grinds to a halt and GUI users around the world are unable to access the app. I believe some heads will be nodding here because I hear about this happening occasionally. T > From: Wjhonson > Then you're misunderstanding what I'm saying. > From: Kevin King > +1. Well stated. > > Woodward, Bob wrote: > > In an active user session where users are obtaining a lock for a > > length of time, you're right. There are lots of times, though, that > > lock intervention is not a benefit. It all depends on the need of the > > application and many situations where I would highly recommend > > using the default locking system of READU. > > From: Wjhonson > > I wouldn't however *recommend* this approach to locking as the user > > can never tell if their terminal is waiting on a lock, or just "hung" > > in some other odd manner, or perhaps processing a batch of something. > > > > So it's rather a nasty trick to play on the user, to just use READU > > without a LOCKED clause ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] Record locks (Unidata 7.2)
One technique that I have used, in the past, has been to save a list of locked ID's and at the end of the program re-try them when all else has finished. Then if they are still locked the program will send a message to me or the operator to alert that there is a locked record. -Original Message- From: u2-users-boun...@listserver.u2ug.org [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Jon Wells Sent: Friday, February 08, 2013 9:57 AM To: U2 Users List Subject: Re: [U2] Record locks (Unidata 7.2) I should add that (in our test account) I switched to the READU statement along with a LOCKED clause -> READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END I locked one of the records in the list I was processing. When the program was working on that record, the CRT statement was executed, and the program moved right along processing the rest of the list; and record I had locked was not updated. Looking through the 'UniBasic Commands Reference' PDF, I found 'RECORDLOCKED (file.var, rec.id.expr)'. Perhaps this could be used within a LOOP to control things, allowing terminal input where the user can choose what to do about the record lock? I've decided to write the data to a new file, so this is no longer a big issue for me. If I had created the program using our vendor's tool kit, the generated code would have added all the appropriate gunk the system uses for record locks. The responses have been interesting as I've been looking for a chance to better understand how Unidata shops handle locks. Thank you, Jon Wells From: Tony Gravagno <3xk547...@sneakemail.com> To: u2-users@listserver.u2ug.org Sent: Friday, February 8, 2013 2:30 AM Subject: Re: [U2] Record locks (Unidata 7.2) I think people understand exactly what you're saying, but disagree. Most applications don't use the more rigorous coding for having a Locked clause that provides additional information to the user, retries, etc. That's not "wrong", it's just not necessary ... depending on the site. That said, when we used to have a lot of people in an office and a dumb terminal beeping was a recognized message to everyone, it was OK (generally) to just do the READU. These days with more alternative UIs, thick-client, thin-client, web services, mobile, etc, there's no one to hear that beep. So for modern development I would agree that you really don't want an unconditional lock hanging around, you want a Locked clause with logic to rollback the transaction and exit gracefully, perhaps with a message sent to the site admin. The penalty for Not having a Locked clause with a new UI is that the port will hang, the UI will receive a timeout (which many clients aren't prepared to process), and the DBMS port could be sitting there indefinitely with no one aware of the condition. This can cascade to multiple ports until suddenly everything grinds to a halt and GUI users around the world are unable to access the app. I believe some heads will be nodding here because I hear about this happening occasionally. T > From: Wjhonson > Then you're misunderstanding what I'm saying. > From: Kevin King > +1. Well stated. > > Woodward, Bob wrote: > > In an active user session where users are obtaining a lock for a > > length of time, you're right. There are lots of times, though, that > > lock intervention is not a benefit. It all depends on the need of the > > application and many situations where I would highly recommend > > using the default locking system of READU. > > From: Wjhonson > > I wouldn't however *recommend* this approach to locking as the user > > can never tell if their terminal is waiting on a lock, or just "hung" > > in some other odd manner, or perhaps processing a batch of something. > > > > So it's rather a nasty trick to play on the user, to just use READU > > without a LOCKED clause ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] Record locks (Unidata 7.2)
Jon the LOCKED clause acts like a Then...else You can only take one branch. So for the locked record, it took the LOCKED branch and ignored the END THEN branch Because the Locked clause is another case you see? Like Readu CASE Locked: do this CASE NotLockedANd Exists: do that CASE NotLockedANDDoesNotExist: do a third thing You understand? This is why you MUST have a LOOPing structure around the Locking. Which is what I sent you the other day. -Original Message- From: Jon Wells To: U2 Users List Sent: Fri, Feb 8, 2013 9:57 am Subject: Re: [U2] Record locks (Unidata 7.2) I should add that (in our test account) I switched to the READU statement along with a LOCKED clause -> READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END I locked one of the records in the list I was processing. When the program was working on that record, the CRT statement was executed, and the program moved right along processing the rest of the list; and record I had locked was not updated. Looking through the 'UniBasic Commands Reference' PDF, I found 'RECORDLOCKED (file.var, rec.id.expr)'. Perhaps this could be used within a LOOP to control things, allowing terminal input where the user can choose what to do about the record lock? I've decided to write the data to a new file, so this is no longer a big issue for me. If I had created the program using our vendor's tool kit, the generated code would have added all the appropriate gunk the system uses for record locks. The responses have been interesting as I've been looking for a chance to better understand how Unidata shops handle locks. Thank you, Jon Wells From: Tony Gravagno <3xk547...@sneakemail.com> To: u2-users@listserver.u2ug.org Sent: Friday, February 8, 2013 2:30 AM Subject: Re: [U2] Record locks (Unidata 7.2) I think people understand exactly what you're saying, but disagree. Most applications don't use the more rigorous coding for having a Locked clause that provides additional information to the user, retries, etc. That's not "wrong", it's just not necessary ... depending on the site. That said, when we used to have a lot of people in an office and a dumb terminal beeping was a recognized message to everyone, it was OK (generally) to just do the READU. These days with more alternative UIs, thick-client, thin-client, web services, mobile, etc, there's no one to hear that beep. So for modern development I would agree that you really don't want an unconditional lock hanging around, you want a Locked clause with logic to rollback the transaction and exit gracefully, perhaps with a message sent to the site admin. The penalty for Not having a Locked clause with a new UI is that the port will hang, the UI will receive a timeout (which many clients aren't prepared to process), and the DBMS port could be sitting there indefinitely with no one aware of the condition. This can cascade to multiple ports until suddenly everything grinds to a halt and GUI users around the world are unable to access the app. I believe some heads will be nodding here because I hear about this happening occasionally. T > From: Wjhonson > Then you're misunderstanding what I'm saying. > From: Kevin King > +1. Well stated. > > Woodward, Bob wrote: > > In an active user session where users are obtaining a lock for a > > length of time, you're right. There are lots of times, though, that > > lock intervention is not a benefit. It all depends on the need of the > > application and many situations where I would highly recommend > > using the default locking system of READU. > > From: Wjhonson > > I wouldn't however *recommend* this approach to locking as the user > > can never tell if their terminal is waiting on a lock, or just "hung" > > in some other odd manner, or perhaps processing a batch of something. > > > > So it's rather a nasty trick to play on the user, to just use READU > > without a LOCKED clause ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] Record locks (Unidata 7.2)
I should add that (in our test account) I switched to the READU statement along with a LOCKED clause -> READU STU.REC FROM STU.FILE, STU.ID LOCKED CRT STU.ID:" RECORD IS LOCKED" END THEN STU.REC<48> = INST.CRED STU.REC<49> = INET.CRED WRITE STU.REC ON STU.FILE, STU.ID END I locked one of the records in the list I was processing. When the program was working on that record, the CRT statement was executed, and the program moved right along processing the rest of the list; and record I had locked was not updated. Looking through the 'UniBasic Commands Reference' PDF, I found 'RECORDLOCKED (file.var, rec.id.expr)'. Perhaps this could be used within a LOOP to control things, allowing terminal input where the user can choose what to do about the record lock? I've decided to write the data to a new file, so this is no longer a big issue for me. If I had created the program using our vendor's tool kit, the generated code would have added all the appropriate gunk the system uses for record locks. The responses have been interesting as I've been looking for a chance to better understand how Unidata shops handle locks. Thank you, Jon Wells From: Tony Gravagno <3xk547...@sneakemail.com> To: u2-users@listserver.u2ug.org Sent: Friday, February 8, 2013 2:30 AM Subject: Re: [U2] Record locks (Unidata 7.2) I think people understand exactly what you're saying, but disagree. Most applications don't use the more rigorous coding for having a Locked clause that provides additional information to the user, retries, etc. That's not "wrong", it's just not necessary ... depending on the site. That said, when we used to have a lot of people in an office and a dumb terminal beeping was a recognized message to everyone, it was OK (generally) to just do the READU. These days with more alternative UIs, thick-client, thin-client, web services, mobile, etc, there's no one to hear that beep. So for modern development I would agree that you really don't want an unconditional lock hanging around, you want a Locked clause with logic to rollback the transaction and exit gracefully, perhaps with a message sent to the site admin. The penalty for Not having a Locked clause with a new UI is that the port will hang, the UI will receive a timeout (which many clients aren't prepared to process), and the DBMS port could be sitting there indefinitely with no one aware of the condition. This can cascade to multiple ports until suddenly everything grinds to a halt and GUI users around the world are unable to access the app. I believe some heads will be nodding here because I hear about this happening occasionally. T > From: Wjhonson > Then you're misunderstanding what I'm saying. > From: Kevin King > +1. Well stated. > > Woodward, Bob wrote: > > In an active user session where users are obtaining a lock for a > > length of time, you're right. There are lots of times, though, that > > lock intervention is not a benefit. It all depends on the need of the > > application and many situations where I would highly recommend > > using the default locking system of READU. > > From: Wjhonson > > I wouldn't however *recommend* this approach to locking as the user > > can never tell if their terminal is waiting on a lock, or just "hung" > > in some other odd manner, or perhaps processing a batch of something. > > > > So it's rather a nasty trick to play on the user, to just use READU > > without a LOCKED clause ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] Record locks (Unidata 7.2)
We don't really have the luxury to rewrite the entire system. But we can fix one program a day -Original Message- From: Wols Lists To: u2-users Sent: Fri, Feb 8, 2013 1:22 am Subject: Re: [U2] Record locks (Unidata 7.2) On 08/02/13 07:30, Tony Gravagno wrote: > I think people understand exactly what you're saying, but disagree. > Most applications don't use the more rigorous coding for having a > Locked clause that provides additional information to the user, > retries, etc. That's not "wrong", it's just not necessary ... > depending on the site. And even in an office, if you code properly, an unprotected READU can make sense. The proper way to program data entry (if you can) is to read everything, get the info from the user, and then RERUN THE TRANSACTION using locks to stash it safely away. That way, you should never get a program hanging on a lock for more than a second or so (I know I know ...) Cheers, Wol ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
Re: [U2] Record locks (Unidata 7.2)
On 08/02/13 07:30, Tony Gravagno wrote: > I think people understand exactly what you're saying, but disagree. > Most applications don't use the more rigorous coding for having a > Locked clause that provides additional information to the user, > retries, etc. That's not "wrong", it's just not necessary ... > depending on the site. And even in an office, if you code properly, an unprotected READU can make sense. The proper way to program data entry (if you can) is to read everything, get the info from the user, and then RERUN THE TRANSACTION using locks to stash it safely away. That way, you should never get a program hanging on a lock for more than a second or so (I know I know ...) Cheers, Wol ___ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users