delphi 3, dbase files, I am using transactions.  why can I post without
error after an insert but the commit causes an EDatabaseError - Data
Structure Corruption.  This only happens when I insert, not on edits!!

database1.starttransaction;
table1.insert;
table1.sskey := newvalue;
table1.namekey := '';
table2.insert;
table2.sskey := newvalue;
table2.namekey := '';
table1.post;
table2.post;
database1.commit;

I've tried restructuring the tables and this does nothing to fix the
problem.  I debuged through and see that DBIEndTran is returning error code
8451.

please anyone that can help explain why this happens!
Thanks,
Michael

I assume you are using cached updates?

Here is a function I use to save changes to all tables on a form. See the
difference between your code, is your trying to insert records within the
transaction. You should be able to just insert and edits records normally, and
then when you want to save all inserts and edits, you start the transaction and
commit them if possible.  There are some good articles in the Delphi Informant
magazine, which I believe you can find stuff from the on the web. The May,
June, and July issues have a 3 part series on using cached updates. I don't
know anything about transactions without using cached updates, so I hope you
are using cached updates...

----------------------------------------------------------------------
function TForm1.ApplyUpdates( Form: TForm ): Boolean;
var
  x: Integer;
begin
  Result := True;
  Session.Databases[0].StartTransaction;
  try
    for x:=0 to Form.ComponentCount-1 do begin
     // Search through and find any TTables
     if Form.Components[x] is TTable then begin
        // If found a table, make sure any changes have been posted.
        if (Form.Components[x] as TTable).State in [dsEdit,dsInsert] then
          (Form.Components[x] as TTable).Post;
        // If using cached updates....
        if (Form.Components[x] as TTable).CachedUpdates = True then
           // and if there are updates pending, apply them
           if (Form.Components[x] as TTable).UpdatesPending = True then
             (Form.Components[x] as TTable).ApplyUpdates;
      end;
    end;
    Session.DataBases[0].Commit;
  except
    Result := False;
    Session.Databases[0].RollBack;
  end;

  for x:=0 to Form.ComponentCount-1 do
    if Form.Components[x] is TTable then
      if (Form.Components[x] as TTable).CachedUpdates = True then
        if (Form.Components[x] as TTable).Active = True then
          (Form.Components[x] as TTable).CommitUpdates; // This is a bad name
for a

// function, since all it does is clear the cache.
end;
--------------------------------------------------------------------------------------

srdan...@hotmail.com
Daniel Raith

I assume you are using cached updates?

Here is a function I use to save changes to all tables on a form. See the
difference between your code, is your trying to insert records within the
transaction. You should be able to just insert and edits records normally, and
then when you want to save all inserts and edits, you start the transaction and
commit them if possible.  There are some good articles in the Delphi Informant
magazine, which I believe you can find stuff from the on the web. The May,
June, and July issues have a 3 part series on using cached updates. I don't
know anything about transactions without using cached updates, so I hope you
are using cached updates...

----------------------------------------------------------------------
function TForm1.ApplyUpdates( Form: TForm ): Boolean;
var
  x: Integer;
begin
  Result := True;
  Session.Databases[0].StartTransaction;
  try
    for x:=0 to Form.ComponentCount-1 do begin
     // Search through and find any TTables
     if Form.Components[x] is TTable then begin
        // If found a table, make sure any changes have been posted.
        if (Form.Components[x] as TTable).State in [dsEdit,dsInsert] then
          (Form.Components[x] as TTable).Post;
        // If using cached updates....
        if (Form.Components[x] as TTable).CachedUpdates = True then
           // and if there are updates pending, apply them
           if (Form.Components[x] as TTable).UpdatesPending = True then
             (Form.Components[x] as TTable).ApplyUpdates;
      end;
    end;
    Session.DataBases[0].Commit;
  except
    Result := False;
    Session.Databases[0].RollBack;
  end;

  for x:=0 to Form.ComponentCount-1 do
    if Form.Components[x] is TTable then
      if (Form.Components[x] as TTable).CachedUpdates = True then
        if (Form.Components[x] as TTable).Active = True then
          (Form.Components[x] as TTable).CommitUpdates; // This is a bad name
for a

// function, since all it does is clear the cache.
end;
--------------------------------------------------------------------------------------

srdan...@hotmail.com
Daniel Raith

I assume you are using cached updates?

Here is a function I use to save changes to all tables on a form. See the
difference between your code, is your trying to insert records within the
transaction. You should be able to just insert and edits records normally, and
then when you want to save all inserts and edits, you start the transaction and
commit them if possible.  There are some good articles in the Delphi Informant
magazine, which I believe you can find stuff from the on the web. The May,
June, and July issues have a 3 part series on using cached updates. I don't
know anything about transactions without using cached updates, so I hope you
are using cached updates...

----------------------------------------------------------------------
function TForm1.ApplyUpdates( Form: TForm ): Boolean;
var
  x: Integer;
begin
  Result := True;
  Session.Databases[0].StartTransaction;
  try
    for x:=0 to Form.ComponentCount-1 do begin
     // Search through and find any TTables
     if Form.Components[x] is TTable then begin
        // If found a table, make sure any changes have been posted.
        if (Form.Components[x] as TTable).State in [dsEdit,dsInsert] then
          (Form.Components[x] as TTable).Post;
        // If using cached updates....
        if (Form.Components[x] as TTable).CachedUpdates = True then
           // and if there are updates pending, apply them
           if (Form.Components[x] as TTable).UpdatesPending = True then
             (Form.Components[x] as TTable).ApplyUpdates;
      end;
    end;
    Session.DataBases[0].Commit;
  except
    Result := False;
    Session.Databases[0].RollBack;
  end;

  for x:=0 to Form.ComponentCount-1 do
    if Form.Components[x] is TTable then
      if (Form.Components[x] as TTable).CachedUpdates = True then
        if (Form.Components[x] as TTable).Active = True then
          (Form.Components[x] as TTable).CommitUpdates; // This is a bad name
for a

// function, since all it does is clear the cache.
end;
--------------------------------------------------------------------------------------

srdan...@hotmail.com
Daniel Raith

Are you inserting into a table shared by other users on a network
containing Win95B machines?  If so, that COULD be your problem.

We've discovered that in Delphi 1 running BDE 2.52 that a Win95b machine
inserting records into a table (paradox) that is shared by other machines
will corrupt the table structure.

Daniel,

No, I am not.  Should I?

Scott,

how do I tell if my machine is a Win95B?  I am running this on a network;
however, I'm the only one running the program.
how do I tell the BDE version that I'm running?

thanks,
Michael

Michael Messerschmidt <rmess...@pheaa.org> wrote in article
<01bcf35f$a81c4940$14239ca4@anxpc01007>...

[this taken from Win95a machine]
Microsoft Windows 95
4.00.950a       <-- here is where you can tell...

As for the version of the BDE you are running, I'm not entirely sure.  I
know what version I am running (v2.52) simply because I pulled it off of
the Borland web site.

If you are really the only one running [your application] on the network,
then I don't think that this is the problem, but I cannot be sure.

- Scott

For the BDE version I believe D2.01 shipped with BDE 3.0.  I d/l'ed BDE
3.5 from www.borland.com.  I am not sure if BDE4.0 shipped with D3 but
it seems so.

Regards, -= Lou Rizzuto =-

Michael Messerschmidt <rmess...@pheaa.org> wrote in article
<01bcf35f$a81c4940$14239ca4@anxpc01007>...

Connie

Scott,

No I am running Win95a.  From what I can tell it looks like I'm running BDE
2.52.  Any other ideas?

Michael

Michael

Mike

Scott,

I don't have any Blobs or Memos in the files, just string and numeric data.

Michael

Scott Hamilton <Sco...@Sensory.Com> wrote in article
<01bcf8d3$be8e0e60$e6332299@hamilton>...