Runing coding in specific order

[secondcircuits]

I have a page that runs an append from Original database to New database, then deletes the originals from Original database. The coding works, I just am concerned about a possible error resulting in lost data later.

DIM Append as P

a_tbl = table.open("[pathalias.adb_path]\scc_inventory_sold")
append.t_db = "[pathalias.adb_path]\scc_inventory"



append.m_key = ""
append.t_key = ""
append.m_filter = ""
append.t_filter = "alltrim(Location) = \"Sold\""
append.type = "All"
append.m_count = 8
append.m_field1 = "Id"
append.m_exp1 = "@Scc_Inventory->Id"
append.m_field2 = "Serialnumber"
append.m_exp2 = "@Scc_Inventory->Serialnumber"
append.m_field3 = "Stockcode"
append.m_exp3 = "@Scc_Inventory->Stockcode"
append.m_field4 = "Location"
append.m_exp4 = "@Scc_Inventory->Location"
append.m_field5 = "Description"
append.m_exp5 = "@Scc_Inventory->Description"
append.m_field6 = "Condition"
append.m_exp6 = "@Scc_Inventory->Condition"
append.m_field7 = "Notes"
append.m_exp7 = "@Scc_Inventory->Notes"
append.m_field8 = "Accessories"
append.m_exp8 = "@Scc_Inventory->Accessories"
append.t_count = 0

a_tbl.append()
a_tbl.close()

a_tbl2 = table.open("[pathalias.adb_path]\scc_inventory")
a_tbl2.delete_range("alltrim(Location) = \"Sold\"")
a_tbl2.close()

The code works and does what it should. Will it always execute properly? First running the append then deleting the original data. Is there a way to force one set of coding to run before the next? I am just concerned that one day it may run delete before the append.

I realize that the safest way is to set this up on separate pages, but that makes it inconvenient and also gives the ability to start loosing or double copying data because of human mistakes.

Any suggestions?

Also thank you to all of those that has suggested or helped in the past with my many many questions. You guys are great

[Steve Wood]

Re: Runing coding in specific order

It will always run in the order the code is written. However, I would be more concerned that the append fails (e.g., a locked table) and then it still runs the delete with success. Maybe a flag somewhere that says "Append Ran OK, Safe To Run The Delete".

[MikeC]

Re: Runing coding in specific order

Steve,
I know this is the web side, but think Alpha code/script runs the same regardless of desktop or web.

It will always run in the order the code is written

Maybe mistaken, but sure seem to remember that code/scripts/operations are all susceptible to timing issues where a latter one can start before a prior one ends--and is the reason to use these inside of functions to insure they cannot conflict as supposedly when a function is encountered, it has to end before anything else can start. (I said supposedly as last week I had two functions in a script that even though the first was not done the second one started...)

Your last suggestion, of course, would be prudent as a safety for not only a crashed script but also for any possible timing issues as well.

Best I guess for me to try and find the threads that pertained to this again--believe it has to do with single and multi-thread situations...

[secondcircuits]

Re: Runing coding in specific order

The last thing that I want to happen is the delete is ran before the append.

Just brainstorming out oud, but could the delete be set up on an if function?

if append successful then run delete
if append error then generate.error()


I do not yet know the if functions well, but will do some reading up on it, if it seems that this would be possible?

[Tim Kiebert]

Re: Runing coding in specific order

Just brainstorming out oud, but could the delete be set up on an if function?

if append successful then run delete
if append error then generate.error()

Yes definitely

I would split the code up into separate user defined functions. One for append and the other for delete. A function has the ability to return a value so in the append function you would test for any errors. If no errors are encountered then let the function return some thing that indicates such like a numeric 1 or character "OK" etc

Then make the running of the delete step conditional on the result of the first step.

if the append failed you will have to figure out which if any records got appended. and deal with that.

It just so happens that the append operation has something built in that can help here and may be sufficient as a control all round. The Append operation can change a value in the record being appended(in the transaction table). So you could have the append operation set the 'Location' field in scc_inventory to 'Appended'. Then have the delete step look for 'Appended instead of 'Sold'. Either before or after the delete you can do a check if there are any records left that still have 'Sold' in the Location field. If yes you know the append did not finish its job and you can investigate. In the mean time the delete will not delete records that have not been appended.

[secondcircuits]

Re: Runing coding in specific order

I was thinking something along this line coming home from work yesterday. The location "Appended" would never be something that is normally used. Also i believe this would give me the ability to place this coding on the a5w page holding the grid, making it an automatic function.

I will try it out today and make sure everything seems to work fine. (with demo data)

Thank you all for the great advice