I have a D2006 compiled app converted from DBISAM3 to EDB. Several
users on XP have a problem in which certain controls (ComboBoxes,
TEdits, TDateTimePicker, TBitButtons) will not show when the app is
started. TMenu, TLabel, TShape and TSpeedButton are not affected. I
don't see the problem here on XP or Vista. The one thing all these
people have in common is that they used an upgrade utilty I wrote to
upgrade their data from DBISAM 3 to EDB tables. Is there any way the
conversion could be causing this? One user was able to resolve the
problem by completely uninstalling and then doing a clean install
without upgrading the tables.

One user has the problem on one XP machine but not the other. The only
difference seems to be the video card. The laptop on which the
software works as intended runs an ATI card, the problem machine uses
an nVidia card.

Michael


I can't see how altering the database could do this since ElevateDB (and DBISAM) are non-visual in nature. It reminds me of a W95/W98 problem with ComCtrls.dll (or whatever it was) where the toolbuttons lost their glyphs.

Depending on what else you do in your upgrade I'd look at the hardware and OS variables first.

Roy Lambert

Michael,

<< I have a D2006 compiled app converted from DBISAM3 to EDB. Several users
on XP have a problem in which certain controls (ComboBoxes, TEdits,
TDateTimePicker, TBitButtons) will not show when the app is started. TMenu,
TLabel, TShape and TSpeedButton are not affected. I don't see the problem
here on XP or Vista. The one thing all these people have in common is that
they used an upgrade utilty I wrote to upgrade their data from DBISAM 3 to
EDB tables. Is there any way the conversion could be causing this? >>

No.  Absolutely not.

--
Tim Young
Elevate Software
www.elevatesoft.com

On Fri, 9 Nov 2007 13:30:02 -0500, "Tim Young [Elevate Software]"
<timyoung@elevatesoft.com> wrote:

>Michael,
>
><< I have a D2006 compiled app converted from DBISAM3 to EDB. Several users
>on XP have a problem in which certain controls (ComboBoxes, TEdits,
>TDateTimePicker, TBitButtons) will not show when the app is started. TMenu,
>TLabel, TShape and TSpeedButton are not affected. I don't see the problem
>here on XP or Vista. The one thing all these people have in common is that
>they used an upgrade utilty I wrote to upgrade their data from DBISAM 3 to
>EDB tables. Is there any way the conversion could be causing this? >>
>
>No.  Absolutely not.

OK I've determined that the missing controls are due to the program's
main form initialization function not running. It won't run if there
is a problem connecting to the database. One customer has found that
the database seems to get corrupted if he closes down the computer
without closing down my app. (This is a normal shutdown or restart,
not pulling the power.) In DataModule.Destroy I close the engine. Is
there something else I should be doing to prevent corruption? The help
file mentions "using specific calls in ElevateDB for selectively
flushing buffers at the operating system level" that sounds like
FlushBuffers in DBISAM but it doesn't seem to be explained anywhere in
the help file.

Michael,

<< OK I've determined that the missing controls are due to the program's
main form initialization function not running. It won't run if there is a
problem connecting to the database. One customer has found that the database
seems to get corrupted if he closes down the computer without closing down
my app. (This is a normal shutdown or restart,
not pulling the power.) >>

Is this Vista ?  If so, then Vista has some issues with killing applications
before they are completely shut down:

http://msdn2.microsoft.com/en-us/library/ms700677.aspx

<< In DataModule.Destroy I close the engine. Is there something else I
should be doing to prevent corruption? The help file mentions "using
specific calls in ElevateDB for selectively flushing buffers at the
operating system level" >>

Where in the help file are you seeing this ?

<< that sounds like FlushBuffers in DBISAM but it doesn't seem to be
explained anywhere in the help file. >>

It is explained here:

http://www.elevatesoft.com/edb1d7_tedbdataset_flushbuffers.htm
http://www.elevatesoft.com/edb1d7_tedbsession_forcebufferflush.htm
http://www.elevatesoft.com/edb1sql_buffering_caching.htm

--
Tim Young
Elevate Software
www.elevatesoft.com

Michael,

And also here:

http://www.elevatesoft.com/edb1d7_connecting_sessions.htm

--
Tim Young
Elevate Software
www.elevatesoft.com

On Fri, 9 Nov 2007 16:27:34 -0500, "Tim Young [Elevate Software]"
<timyoung@elevatesoft.com> wrote:

>Michael,
>
><< OK I've determined that the missing controls are due to the program's
>main form initialization function not running. It won't run if there is a
>problem connecting to the database. One customer has found that the database
>seems to get corrupted if he closes down the computer without closing down
>my app. (This is a normal shutdown or restart,
>not pulling the power.) >>
>
>Is this Vista ?  If so, then Vista has some issues with killing applications
>before they are completely shut down:

No XP.

>http://msdn2.microsoft.com/en-us/library/ms700677.aspx
>
><< In DataModule.Destroy I close the engine. Is there something else I
>should be doing to prevent corruption? The help file mentions "using
>specific calls in ElevateDB for selectively flushing buffers at the
>operating system level" >>
>
>Where in the help file are you seeing this ?

Right here:
http://www.elevatesoft.com/edb1sql_buffering_caching.htm

><< that sounds like FlushBuffers in DBISAM but it doesn't seem to be
>explained anywhere in the help file. >>
>
>It is explained here:
>
>http://www.elevatesoft.com/edb1d7_tedbdataset_flushbuffers.htm
>http://www.elevatesoft.com/edb1d7_tedbsession_forcebufferflush.htm
>http://www.elevatesoft.com/edb1sql_buffering_caching.htm

OK but I rarely use tables anymore just UPDATE/INSERT queries. These
queries always flush automatically don't they?

Michael,

<< OK but I rarely use tables anymore just UPDATE/INSERT queries. These
queries always flush automatically don't they? >>

Not in ElevateDB, no.  In DBISAM they did, but with ElevateDB we decided to
make them behave just like a navigational insert, update, or delete.

--
Tim Young
Elevate Software
www.elevatesoft.com