Let's work together to solve a difficult problem

maweike

The following code is the code of ado dynamically linking the sql database, but it is not connected, I don't know what the reason is, everyone helps to solve it together. The error is that the exception dialog box is skipped, which says, 'Unable to open the database Book_Data requested during login, login failed'
code show as below:

var
Logintimes: integer = 0;

procedure TEnter_F.FormCreate (Sender: TObject);
var
DLYH_Q: TADOQuery;
ADOCommand: TADOCommand;
  s, DataPath: string;
begin
 Connect: = TADOConnection.Create (nil);
Connect.ConnectionString: = 'Provider = SQLOLEDB; Integrated Security = SSPI; Persist Security Info = False; Initial Catalog = Book_Data';
Connect.LoginPrompt: = false;
try
Connect.Connected: = true;
except
 ADOCommand: = TADOCommand.Create (nil);
ADOCommand.ConnectionString: = 'Provider = SQLOLEDB.1; Integrated Security = SSPI; Persist Security Info = False';
DataPath: = ExtractFilePath (Application.ExeName);
s: = 'EXEC sp_attach_db @dbname = N' + char (39) + 'Book_Data' + char (39) + ',' +
'@ filename1 = N' + char (39) + DataPath + 'Book_Data.MDF' + char (39) +
',' + '@ filename2 = N' + char (39) + DataPath + 'Book_Data.LDF' + char (39);
ADOCommand.CommandText: = s;
  ADOCommand.Execute ();
end;

 DLYH_Q: = TADOQuery.Create (nil);
DLYH_Q.Connection: = Connect;
DLYH_Q.SQL.Clear;
DLYH_Q.SQL.Add ('select name from logged in user');
DLYH_Q.Open;
if DLYH_Q.RecordCount> 0 then
while not DLYH_Q.Eof do
begin
XM_CB.Items.Add (DLYH_Q.FieldValues ​​['Name']);
DLYH_Q.Next;
end;
DLYH_Q.Close;
FreeAndNil (DLYH_Q);
  XM_CB.ItemIndex: = 0;
end;

remmus

Forget it for you. .

maweike

Why did n’t anyone answer, would n’t it?

madwww

In your Connect.ConnectionString: = 'Provider = SQLOLEDB; Integrated Security = SSPI; Persist Security Info = False; Initial Catalog = Book_Data' ;, no data source is specified, no user ID is specified, no password is specified, how can it be possible on?

maweike

How to get the host name dynamically

njy7648

How to get the host name dynamically
======================================================== ===========================
What does this have to do with your hostname? Either get the database dynamically:

ADOCommand: = TADOCommand.Create (nil);
ADOCommand.ConnectionString: = PromptDataSource (Handle, DataConnection.ConnectionString);

maweike

Is your above a dynamic link? It doesn't seem to be a connection. It doesn't specify the database name.

stevevai

Database server and database are not specified in ConnectionString

njy7648

Is your above a dynamic link? It doesn't seem to be a connection. It doesn't specify the database name.
======================================================== ================================
Don't know if you try it

njy7648

ADOCommand.ConnectionString: = PromptDataSource (Handle, DataConnection.ConnectionString);
To change the above:
ADOCommand.ConnectionString: = PromptDataSource (Handle, ADOCommand.ConnectionString);
or:
ADOCommand.ConnectionString: = PromptDataSource (Handle, ‘’);
Where Handle is the window handle