To add to Dan's ideas, it can also happen if you use setItemStatus to set a
row or columns status to a new value (i.e. notModified! or DataModified!).
Dan's SQL Spy idea will be your best bet. If you are getting nothing but
?'s where there should be values in the SQL, turn off Binding when you
connect to the database. It will slow down the SQL but for testing it's
worth it.
D
----- Original Message -----
From: Griffith, Daniel M. <[EMAIL PROTECTED]>
To: 'Sawant Prasad' <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>
Sent: Tuesday, August 29, 2000 7:53 AM
Subject: RE: PFCSIG Datawindow Error while updating
> This doesn't sound like a PFC question, but a basic PB one. But, it
> might help you to enable the PFC SQLSpy to determine the WHERE clause that
> is being executed.
>
> It sounds like the DataWindow Update Properties are not set
consistently
> with the way your application is behaving. Basically, when PB performs
the
> Update() function, it executes a SQL UPDATE statement. The DW Update
> Properties specify which columns to include in the WHERE clause for that
> UPDATE.
>
> It is there to help you detect when two people are attempting to update
> the same row of data. Image two people do retrieves of the same row.
Some
> time later, the first person updates the data. Some time after that, the
> other person attempts to update the data. The WHERE clause determines
which
> row to update, and depending on the settings, the UPDATE statement may
fail
> because the row is not found. That leads to the 'row changed between
> retrieve and update' message.
>
> I'm assuming you currently have the update properties set to include all
> columns.
> Your options include:
> 1. Change the WHERE clause to include only modified columns. This way,
> you will only encounter the message when two people edit the same columns
in
> the same row. (With all columns, you get the message even if the persons
> update different columns on the same row.)
> 2. Change the WHERE clause to include only key columns. This way, you
> will only encounter the message when the first person deletes the row that
> the second person later tries to update. Note that many people think that
> setting it to 'key columns' eliminates the problem--it does not.
>
> It is also possible that embedded SQL in your code is updating the row
> before the DataWindow's update function is executed. This would be the
same
> as if another user had updated the data.
> Another possibility, less common, is that you retrieve the data, some
> column(s) that are in the UPDATE WHERE clause change in the DataWindow,
your
> code performs a ResetUpdate(), again modifies the column(s) in the WHERE
> clause and *then* the Update() function is called. After a ResetUpdate(),
> PB will use the values in the DW's "Original" buffer in the WHERE clause.
> Because your code changed them, they no longer match what's on the server,
> which again leads to the UPDATE statement failing.
> Actually, it's not common in general, but I do see it when developers
> call the Update() function with no parameters, instead of Update(false,
> false) and then managing the flags themselves.
> Another somewhat common defective technique that leads to this is
setting
> a row's attributes after adding a new row, then generating a unique
primary
> key id, then calling resetUpdate() without writing the "blank" row to the
> server. This would prevent a "do you want to save prompt" from appearing
> unless the user changes something. The problem is that once the user
> changes something, and the Update() function is called, PB treats it like
an
> UPDATE, instead of an INSERT. And since the row was never written to the
> server, the UPDATE fails (even if you have the WHERE clause properties set
> to key only).
>
> More information on this can be found in the PowerBuilder online books
> and training materials.
>
> Have a nice day,
> --dang
>
>
> -----Original Message-----
> From: Sawant Prasad [mailto:[EMAIL PROTECTED]]
> Sent: Tuesday, August 29, 2000 05:19
> To: [EMAIL PROTECTED]
> Subject: PFCSIG Datawindow Error while updating
>
>
> Can u please help me.
> When i am updating a datawindow i get the following error.
>
> Datawindow Error
> Row changed between retrieve and update.
>
> Can anyone provide me the solution at the earliest.
>
> This error is not regular. It comes rarely.
>
> Thanking you in advance
>
> Prasad Sawant
> email - [EMAIL PROTECTED]
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ADDRESS
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pfcsig
> > SEND ALL OTHER INQUIRES TO [EMAIL PROTECTED]
>
> [EMAIL PROTECTED] HOSTED BY IIGG, INC. FOR HELP WITH LIST SERVE COMMANDS, ADDRESS
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