Cannot connect to DB

[Bobster]

DAC 7.6.12; Delphi XE2, Update 4, HotFix 1; Windows 7.6.1, Build 7601, SP1.

I can connect from the IDE, but using the same params and whether or not LoginPrompt is True, when I try to connect at runtime I get:

'Cannot create TCP/IP socket: The requested service provider could not be loaded or initialized. Socket error code 10106.'

Please tell me what I am missing. Thanks.

[DemetrionQ]

Hello.

Detailed information about the "WSAEPROVIDERFAILEDINIT 10106" error can be read in MSDN.
The work of your IDE is probably blocked by your Firewall or other similar programs (such as Anti-Malware). Please check your Firewall settings. Also, try adding your IDE to the Firewall exclusion list.

[Bobster]

Thanks for your response. I tried your suggestions re firewall, including dropping the firewall and suspending real-time protection on my AV package: same result. I have spent the last day or so since your response researching this further without an MSDN subscription. I tried starting Winsock using WSAStartup; completes successfully. I cannot get control back using try/except around the Connect so I cannot get any further details on the error. Program runs fine from the executable, just not from the debugger. I could use Embedded during development and then switch but I am not entirely comfortable with that. I will limp along until I limp to the finish line or I come across a solution. If you have any other insights I would be grateful for them. Thanks again.

[DemetrionQ]

Hello.

Please run the following code, and check if the error occurs:

Code: Select all

#include <WinSock.h>
...
{
  Integer Sd, Res;
  WSADATA WsaData;
  String LastError;

  Res = WSAStartup(0x0202, &WsaData);
  if(Res != 0){
	TVarRec vr[] = {Res};
	LastError = Sysutils::Format("WSAStartup failed'#$D#$A'Socket Error Code: %d", vr,1);
	throw Exception(LastError);
  }

  Sd = socket(AF_INET, SOCK_STREAM, 0);
  if(Sd == SOCKET_ERROR){
	TVarRec vr[] = {SysErrorMessage(WSAGetLastError()), WSAGetLastError(), WSAGetLastError()};
	LastError = Sysutils::Format("Cannot create TCP/IP socket:'#$D#$A'%s.'#$D#$A'Socket Error Code: %d($%X)", vr, 3);
	throw Exception(LastError);
  }
}

[Bobster]

I have to admit that my C++ experience is limited and I don't even have a C++ compiler installed, although if I did I think I could do this. Could you send me Delphi code or an executable? I hate to be a pest but that's where I'm at. Thank you.

Bob

[DemetrionQ]

Hello.

I am sorry, it was my mistake.
Please run the following code, and check if the error occurs:

Code: Select all

uses WinSock;
...
var
  Sd, Res: integer;
  LastError : string;
  WsaData: TWSAData;
begin
  Res := WSAStartup($0202, WsaData);
  if Res <> 0 then begin
    LastError := Format('WSAStartup failed'#$D#$A'Socket Error Code: %d', [Res]);
    raise Exception.Create(LastError);
  end;

  Sd := socket(AF_INET, SOCK_STREAM, 0);
  if Sd = SOCKET_ERROR then begin
    LastError := Format('Cannot create TCP/IP socket:'#$D#$A'%s.'#$D#$A'Socket Error Code: %d($%X)', [SysErrorMessage(WSAGetLastError), WSAGetLastError, WSAGetLastError]);
    raise Exception.Create(LastError);
  end;
end;

[Bobster]

Thanks much. It runs without error.

[DemetrionQ]

Hello.

Please try the following:
- uninstall MyDAC;
- delete all *dac*.bpl , *crcontrols*.bpl files from your computer;
- search all DAC units on your computer, such as MemData.dcu, MemDS.dcu, DBAccess.dcu, MyClasses.dcu, CRGrid.dcu etc., and delete them.
- install MyDAC.

MyDAC distribution includes a demo project located in the "MyDacDemo" folder in Demos of MyDAC. Check if the problem can be reproduced on this demo project.

[Bobster]

I ran demo and it connected successfully. Following is the code I use for my connect, which I would normally run with LoginPrompt := False:

procedure ConnectToDB(dbc: TMyConnection);
begin
with dbc do begin
Database := DBNAME;
Options.Embedded := False;
Options.Direct := True;
Options.NullForZeroDelphiDate := True;
Server := 'localhost';
Port := 3306;
Username := currentun;
Password := GetPWForLogin(SITE_PW);
LoginPrompt := True;
Connect;
end;
end;

I just noticed for the first time that this code was not even being executed. I turned off optimization and now it is executing but makes no difference. I can change whatever I want in that proc and the dialog remains unchanged. I have found discussion in the forum that tells me this is "normal". I don't understand why but before I uninstall, etc. I will write a custom dialog. I appreciate your support.

Bob

[DemetrionQ]

Hello.

By default, the standard connection dialog displays data of the last successful connection saved in the registry. If you need to disable this specificity, set the TMyConnectDialog.StoreLogInfo property to False, like this:

Code: Select all

  MyConnectDialog1.StoreLogInfo := False;

If you want to create a custom connection dialog, you can use the ConnectDialog demo of MyDAC demo project.

[Bobster]

The StoreLogInfo property is not published and I don't have the source code for DBAccess. Am I out of luck?

[DemetrionQ]

Hello.

The TMyConnectDialog.StoreLogInfo property is published. This is a property of the TMyConnectDialog class, please make sure that you are looking for it in this class.

[Bobster]

Here is what I am trying:

procedure ConnectToDB(dbc: TMyConnection);
begin
with dbc do begin
TMyConnectDialog.StoreLogInfo := False;
.
.
.
[DCC Error] DBOps.pas(242): E2233 Property 'StoreLogInfo' inaccessible here

[Bobster]

Demetrion,

Please ignore my last post. The light finally dawned. I created an instance of TMyConnectDialog, hooked things up, and all is well. That's the good news. The bad news is that I still get the socket exception and can't connect. I will take your advice and uninstall, delete files, and start from scratch. Thanks for your patience.

Bob

[Bobster]

Demetrion,

This is my version of mea culpa. I solved the problem in the following way:

After many trials/errors, reinstall Devart, upgrade MySQL to version 5.6, scratching head, cussing and worse, I looked at the Options for my project. I discovered under the Debugger/Environment Block I had overridden the PATH variable by adding a folder in which was located a version of libmysqld.dll dated 3/22/2012. I did this eons ago for now-unknown reasons when I was using the embedded server. I eliminated the override and voila, success. I wish I understood all I know about this stuff.

Thanks again for your help. You steered me in some directions that I might not have discovered on my own; e.g. MyDacDemo. I am off to start coding again.

Bob