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Hi All I have problem accessing the local database in the simple way.
The program just read register and then test whether the DB can be accessed.
I have two dll in my development folder along with the program I built.
I also have path directed to dll files used in Borland Delphi program

I am using WinXP, MySQL 5 and DBExpress.

But the problem is that it gives two errors:
So here it goes...
1) "Missing DriverName property"

I would not do 2) but because of 1) so I have to do 2) in add SQLConnection in order to test

2) "Unable to load libmySQL.dll"

Here's the code
{code}
unit testDB_DSN;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ColorButton, Registry, checkDSN_DB, DBXpress, DB,
SqlExpr;

type
TForm1 = class(TForm)
edit_DSN: TEdit;
btn_DSN: TColorButton;
btn_Stop: TColorButton;
SQLConnection1: TSQLConnection;
procedure btn_DSNClick(Sender: TObject);
procedure btn_StopClick(Sender: TObject);
//procedure FormCreate(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }

end;

var
Form1: TForm1;
implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
edit_DSN.SetFocus;
end;

procedure TForm1.btn_DSNClick(Sender: TObject);
var name_DSN, source_key1, source_key2, value_DATABASE, value_SERVER : string;
checkDBConnect : integer;
regA : TRegistry;

begin
source_key1 := '\SOFTWARE\ODBC\ODBC.INI\;
name_DSN := edit_DSN.Text;
source_key2 := source_key1 + name_DSN;
regA := TRegistry.Create;// create an TRegistry object before reading
regA.RootKey := HKEY_LOCAL_MACHINE;// That's where information about DSN are located.


//Test the working of DSN in registry
if regA.OpenKey(source_key2, false)then
begin
value_DATABASE := regA.ReadString('DATABASE'); //read the string of the DATABASE key.
value_SERVER := regA.ReadString('SERVER'); //read the string of the SERVER key.
value_DRV := regA.ReadString('DRIVER'); //read the string of the DRIVER key.

//showmessage('Database = '+value_DATABASE+' and '+'Server = '+value_SERVER);
regA.CloseKey; //Close the key after use.

//Test the working of connecttion to DB
checkDBConnect := testDSNDB(value_DATABASE, value_SERVER, value_DRV);
if(checkDBConnect = 0) then
showMessage('Successful! The DSN '+ name_DSN +' is correct and able to connect to '+ value_DATABASE +' @ '+value_SERVER+' Server.')
else
showMessage('DB does not exist for DSN '+ name_DSN+'.');
end
else
//failed: 'DSN '+ name of DSN + ' does not exist or might have been wrongly spelt.'
ShowMessage('DSN '''+name_DSN + ''' does not exist or might have been wrongly spelt.');
begin
regA.Free;
edit_DSN.Clear();
edit_DSN.SetFocus;
// set this control in focus after clearing all the input
//so that it can be entered immediately.
end;
end;

procedure TForm1.btn_StopClick(Sender: TObject);
begin
close; // Use this "Close" command to terminate the running of the program.
end;

end.

{code}



{code}
unit checkDSN_DB;

interface

uses SqlExpr, DB;

//declaration in the interface
function testDSNDB(str_DB, str_SVR, str_DRV : string): integer;
//add this function under interface so that this function can be seen by other units.

implementation

function testDSNDB(str_DB, str_SVR, st_DRV : string): integer;
var db_Connect : TSQLConnection;
begin

db_Connect := TSQLConnection.Create(nil);

try
db_Connect.Params.Values['DriverName']:=str_DRV;//Driver
db_Connect.Params.Values['User_Name'] := '';//mk10basicjig1
db_Connect.Params.Values['Password'] := '';//basicjig1
db_Connect.Params.Values['HostName'] := str_SVR;//HostName
db_Connect.Params.Values['Database'] := str_DB;//DatabaseName
db_Connect.Params.Values['BlobSize'] := '-1';
db_Connect.Params.Values['LocaleCode'] := '0000';
db_Connect.Open;

result := 0;
except
result :=1;
end;
db_Connect.Free;
end;
end.

{code}

Pls advise the solution
Thank you
Clement

Hello,

1. This error means that you didn't set the TSQLConnection.DriverName property.
2. This error means that there is no libmysql.dll in the System32 directory. You should place libmysql.dll to the C:\Windows\System32 directory.

Here are two code examples that demonstrate the correct ways to establish connection to MySQL server:
1. using libmysql.dll :2. without using libmysql.dll , direct connection:It's better to use direct connection, because in this case you don't need libmysql.dll. Also you will have better performance.