roleks...
Для возможной отмены retrieve.
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Подскажите, куда копать?
Копать можно сюда
PowerBuilder Help SQLPreview event (DataWindows)

Description

Occurs immediately before a SQL statement is submitted to the DBMS. Functions that trigger DBMS activity are Retrieve, Update, and ReselectRow.
PowerBuilder event information
Event ID: pbm_dwnsql

Argument Description
request SQLPreviewFunction by value. The function that initiated the database activity.For a list of valid values, see SQLPreviewFunction.
sqltype SQLPreviewType by value. The type of SQL statement being sent to the DBMS.For a list of valid values, see SQLPreviewType .
sqlsyntax String by value. The full text of the SQL statement.
buffer DWBuffer by value. The buffer containing the row involved in the database activity. For a list of valid values, see DWBuffer.
row Long by value. The number of the row involved in the database activity, that is, the row being updated, selected, inserted, or deleted.
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Return value

Set the return code to affect the outcome of the event:

0 Continue processing
1 Stop processing
2 Skip this request and execute the next request

For information on setting the return code in a particular environment, see "About return values for DataWindow events".

Usage

Some uses for the sqlsyntax argument are:

· Changing the SQL to be executed (you can get the value of sqlsyntax, modify it, and call SetSQLPreview)
· Keeping a record (you can write the SQL statement to a log file)

Reported row number The row number stored in row is the number of the row in the buffer, not the number the row had when it was retrieved into the DataWindow object.
If the row that caused the error is in the Filter buffer, you must unfilter it if you want the user to correct the problem.

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Но я тоже не понимаю, почему вы так упорно не хотите сохранить аргументы в собственном коде, который обращается к встроенной функции билдера.