🚀 go-pugleaf

>ADOConnection1->ConnectOptions = coAsyncConnect;
Remove this line. If connection is really asynchrounous you should wait when
connection will be establised.

>     ADOConnection1->ConnectionString =
"Provider=Microsoft.Jet.OLEDB.4.0;";
>     ADOConnection1->ConnectionString = ADOConnection1->ConnectionString +
> "Data Source=";
>     ADOConnection1->ConnectionString = ADOConnection1->ConnectionString +
> "00B0D0F6FF9D.MDB";
>     ADOConnection1->ConnectionString = ADOConnection1->ConnectionString +
> ";Persist Security Info=False";
Do not do like this. Assigning connection string value does not only concat
internal string but also some other processing. Set connection string at
once - if you need construct internal AnsiString or WideString variable and
assign it to ConnectionString property.

>     ADODataSet1->LockType = ltReadOnly ;
>     ADODataSet2->LockType = ltBatchOptimistic;
You do not need batch updates.

>Other code.
You do many useless things. The best way is to execute SQL query like:

DELETE * FROM [TableName] WHERE ID='...'

for every table you need. You may use ADOConnection1->Execute() for this.
Note brackets around table name - they are required in case table name is
one of keywords. ID='...' should be constructed as UID = ... + "ID=" +
QuotedStr(ID), this is required if you have quote char inside ID value, you
may use AnsiQuotedStr.

>         if (ADODataSet1->RecordCount > 0)
>             ADODataSet2->Clone(ADODataSet1);
This will not copy data, it will clone cursor and will not change data in
database, use SQL query like:

Insert * into [DstTable] from [SrcTable] in "C:\\Temp\\SrcDB.mdb"

Table structrure must be equal for DstTable and SrcTable. You may need
execute "Delete * from [DstTable]" if you need to empty DstTable first.

//----------------------
Regards,
Viatcheslav V. Vassiliev
http://www.oledbdirect.com
The fastest way to access MS SQL Server,
MS Jet (Access) and Interbase (through OLEDB)


"Louie Athanasiadis" <la@uow.edu.au> �������/�������� � �������� ���������:
news:3f6fc7b9@newsgroups.borland.com...
> Hello all
> I am writing a program that accepts Access database files from machines in
> my faculty and stores the files under the machines MAC address (this
works)
> A thread then tries to merge each incoming Access database with the main
> Access database. It tries to delete the old data stored in each table in
the
> main database and then merge in the data provided by the Access database
> (that was upload) into the main table. I have tried various ways of doing
> this, but get various error conditions and the program fails, it has to do
> with write permissions (or what ever with the main database) . The line
with
> /****/ mark below fails with an exception
> "Current Recordset does not support updating. This may be a limitation of
> the provider, or of the selected locktype"
>
> I have tried everything I know ( new to ADO programming - new to any
> Database programing on C++ Builder). Any help welcomed. My merge code is
> below
>
>
>
>
>
>
> void __fastcall TForm1::testButtonClick(TObject *Sender)
> {
>     TStrings *TableList = new TStringList;
>     TStrings *FieldList = new TStringList;
>     AnsiString str1;
>     AnsiString str2;
>     AnsiString str3;
>     AnsiString ID;
>     AnsiString UID;
>     AnsiString ColumnName;
>     int i;
>     int j;
>
>     ADOConnection1->ConnectOptions = coAsyncConnect;
>     ADOConnection1->Close();
>     ADOConnection1->ConnectionString =
"Provider=Microsoft.Jet.OLEDB.4.0;";
>     ADOConnection1->ConnectionString = ADOConnection1->ConnectionString +
> "Data Source=";
>     ADOConnection1->ConnectionString = ADOConnection1->ConnectionString +
> "00B0D0F6FF9D.MDB";
>     ADOConnection1->ConnectionString = ADOConnection1->ConnectionString +
> ";Persist Security Info=False";
>     ADOConnection1->Connected = true;
>     ADOConnection1->Open();
>
>     ADOConnection2->ConnectOptions = coAsyncConnect;
>     ADOConnection2->Close();
>     ADOConnection2->Mode = cmReadWrite;
>     ADOConnection2->ConnectionString =
"Provider=Microsoft.Jet.OLEDB.4.0;";
>     ADOConnection2->ConnectionString = ADOConnection2->ConnectionString +
"D
> ata Source=";
>     ADOConnection2->ConnectionString = ADOConnection2->ConnectionString +
> "SOSOS.MDB";
>     ADOConnection2->ConnectionString = ADOConnection2->ConnectionString +
> ";Persist Security Info=False";
>     ADOConnection2->Connected = true;
>     ADOConnection2->Open();
>
>     ADOConnection2->GetTableNames(TableList, false);
>     ADODataSet1->LockType = ltReadOnly ;
>     ADODataSet2->LockType = ltBatchOptimistic;
>     ADOCommand1->CommandText = "Select * from SOS";
>     ADODataSet1->Recordset = ADOCommand1->Execute();
>
>     str1 = ADODataSet1->Fields->Fields[0]->AsString;
>     str2 = ADODataSet1->Fields->Fields[1]->AsString;
>     str3 = ADODataSet1->Fields->Fields[4]->AsString;
>     ID = str1;
>     UID = str2 +  "\\" + str3;
>
>     for ( i = 0; i < TableList->Count; i++)
>     {
>         if (TableList->Strings[i] == "Users" )
>             ADOCommand1->CommandText = "Select * from Users where
UserID='"
> + UID + "'";
>         else
>             ADOCommand1->CommandText = "Select * from " +
> TableList->Strings[i];
>         ADODataSet1->Recordset = ADOCommand1->Execute();
>         ADODataSet1->GetFieldNames(FieldList);
>
>         if (TableList->Strings[i] == "Users")
>             ADOCommand2->CommandText = "Select * from Users where
UserID='"
> + UID + "'" ;
>         else
>             ADOCommand2->CommandText = "Select * from " +
> TableList->Strings[i]+ " where " + FieldList->Strings[0] + "='" + ID +
"'";
>
>
>         ADODataSet2->Recordset = ADOCommand2->Execute();
>
>
>        if (TableList->Strings[i] != "Users" )
>             ADODataSet2->DeleteRecords(arAll);
> /**********************************/
>
>         if (ADODataSet1->RecordCount > 0)
>             ADODataSet2->Clone(ADODataSet1);
>         ADODataSet2->Post();
>
> //        ADODataSet2->UpdateBatch(arAll);
>
>     }
>     ADOConnection1->Close();
>     ADOConnection2->Close();
>
> }
>
>