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Asked: 2026-05-10T23:22:46+00:00

I am new to threads and in need of help. I have a data

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I am new to threads and in need of help. I have a data entry app that takes an exorbitant amount of time to insert a new record(i.e 50-75 seconds). So my solution was to send an insert statement out via a ThreadPool and allow the user to begin entering the data for the record while that insert which returns a new record ID while that insert is running. My problem is that a user can hit save before the new ID is returned from that insert.

I tried putting in a Boolean variable which get set to true via an event from that thread when it is safe to save. I then put in 

while (safeToSave == false)   {       Thread.Sleep(200)   }

I think that is a bad idea. If i run the save method before that tread returns, it gets stuck.

So my questions are:

  1. Is there a better way of doing this?
  2. What am I doing wrong here?

Thanks for any help.
Doug

Edit for more information:

It is doing an insert into a very large (approaching max size) FoxPro database. The file has about 200 fields and almost as many indexes on it.
And before you ask, no I cannot change the structure of it as it was here before I was and there is a ton of legacy code hitting it. The first problem is, in order to get a new ID I must first find the max(id) in the table then increment and checksum it. That takes about 45 seconds. Then the first insert is simply and insert of that new id and an enterdate field. This table is not/ cannot be put into a DBC so that rules out auto-generating ids and the like.

@joshua.ewer
You have the proccess correct and I think for the short term I will just disable the save button, but I will be looking into your idea of passing it into a queue. Do you have any references to MSMQ that I should take a look at?

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  1. Everyone else, including you, addressed the core problems (insert time, why you’re doing an insert, then update), so I’ll stick with just the technical concerns with your proposed solution. So, if I get the flow right:

    • Thread 1: Start data entry for record

    • Thread 2: Background calls to DB to retrieve new Id

    • The save button is always enabled, if user tries to save before Thread 2 completes, you put #1 to sleep for 200 ms?

    The simplest, not best, answer is to just have the button disabled, and have that thread make a callback to a delegate that enables the button. They can’t start the update operation until you’re sure things are set up appropriately.

    Though, I think a much better solution (though it might be overblown if you’re just building a Q&D front end to FoxPro), would be to throw those save operations into a queue. The user can key as quickly as possible, then the requests are put into something like MSMQ and they can complete in their own time asynchronously.

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