Hi Cosmin,

> I'm learning ASP.NET and in the process I need to learn ADO.NET; The 
> syntax for defining and using a SQL query that makes use of parameters 
> seems really difficult to me, so I hope I'm actually missing something.

I'm using a special routine that I wrote to add parameters to a 
parameterised query.

>   X := FbCommand.Create('SELECT * FROM TAB WHERE ID=?', Connection, 
> Transaction);
>   X.Parameters.Add('', DbType.&String).Value := '7';

This is what I would do:

   Command := BdpCommand.Create('SELECT * FROM TAB WHERE ID = ?',
     Connection, Transaction);

   // add parameters, assume ID of type String, length 15
   AddParameterToCommand(Command, 'ID', BdpType.&String, 15, '42');


With the following support routine:

   procedure AddParameterToCommand(var Command: BdpCommand;
     const Name: String;
     &Type: BdpType; Size: Integer; Value: TObject);
   var
     Parameter: Borland.Data.Common.BdpParameter;
   begin
     Parameter := BdpParameter.Create(Name, &Type, Size);
     Parameter.Value := Value;
     Parameter.Direction := ParameterDirection.Input;
     Parameter.SourceColumn := Name;
     Command.Parameters.Add(Parameter);
     {$IFDEF DEBUG}
     context.trace.Write('Parameter ' + Parameter.ParameterName +
        ' = [' + Parameter.Value.ToString + ']')
     {$ENDIF}
   end;

As you can see, the connection to the SourceColumn will ensure that you 
can even call AddParameterToCommand in the "wrong" order (of parameters) 
is you wish.

> Am I missing something? I sure hope I'm missing something...

Described and used in more detail in my ASP.NET courseware manuals by 
the way.

> Thanks,
> Cosmin Prund

Groetjes,
           Bob Swart

-- 
Bob Swart Training & Consultancy (eBob42.com)  Forever Loyal to Delphi
Blog: http://www.drbob42.com/blog - RSS: http://drbob42.com/weblog.xml
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