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From "Petrula, Dan" <DPetr...@thezenith.com>
Subject RE: How to monitor progress during data import
Date Thu, 27 Jul 2006 22:16:03 GMT
There are two ways to attack this problem. Both ways use Swing and the
JPogressBar. The easiest way is to use
the 'setIndeterminate(true) method and you will get a little bar that moves
back and forth while the file is 
being imported. Set it up in a separate thread and when it the import is
complete the thread will end and use 
setIndeterminate(false) and it will stop. I use this for both the backup and
restore funcions for Derby. Another way 
is to count the number of bytes coming in as you read your text file. I have
the code to do this at home, which I
can give you tomorrow, but I suggest the first method. Your user doesn't
really need to know how much has been 
copied, but only that something is being done. If the procedure will take
more than five minutes then I could see
the need. But if you need to do it, I will give you a way to approach this


-----Original Message-----
From: Fantry, John [mailto:JFantry@analogic.com] 
Sent: Wednesday, July 26, 2006 9:00 AM
To: Derby Discussion; mikem_app@sbcglobal.net
Subject: RE: How to monitor progress during data import

I am importing the data using the built in system procedure
SYSCS_UTIL.SYSCS_IMPORT_TABLE.  This procedure takes the name of the file to
import as an argument.  Derby opens the file using whatever mechanism it
wants.  I don't have an opportunity to wrap the stream myself.

-----Original Message-----
From: Mike Matrigali [mailto:mikem_app@sbcglobal.net]

Sent: Wednesday, July 26, 2006 11:27 AM
To: Derby Discussion
Subject: Re: How to monitor progress during data import

Andreas Korneliussen wrote:
> Fantry, John wrote:

>> I am using Derby to import a large text file into a table.  I would

>> like to be able to display a progress dialog to the user while the

>> import is processing.  In order to provide a useful progress bar I

>> need to be able to calculate the % complete of the import procedure.

>> Does anyone know if this can be done?  The table is locked during the

>> import so I can't execute any SELECT COUNT(*) statements in a

>> thread.  Perhaps Derby outputs some statistics to a log file?  I did

>> stumble across the RunTimeStatistics attribute in the Derby docs, but

>> this attribute is only meaningful after the import is complete.  I

>> need insight into the import procedure while it's executing.  Any



> Have you tried running the SELECT COUNT (*) statement using

> isolation level "read-uncommitted " ?
Do note that derby must scan all the rows in the table to execute

count(*), so checking on the progress using count(*) is a significant
overhead depending on the size of the table.

For your application it may be possible to layer a stream on top of the file
which could tell your app how much has been read while otherwise just
passing the bytes from the file to derby.

> Regards
> Andreas



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