Devart Forums

Code: Select all

 //Initialization
 TSQLConnection *SQLConnection;
 SQLConnection=new TSQLConnection(NULL);
 
 SQLConnection->ConnectionName = "MySQL by Core Lab";
 SQLConnection->DriverName = "MySQL by Core Lab";
 SQLConnection->GetDriverFunc = "getSQLDriverMySQL";
 SQLConnection->LibraryName = "dbexpmda30.dll";
 SQLConnection->LoginPrompt = False;
 SQLConnection->Params->Add("BlobSize=-1");
 SQLConnection->Params->Add("HostName=localhost");
 SQLConnection->Params->Add("DataBase=datos");
 SQLConnection->Params->Add("DriverName=MySQL by Core Lab");
 SQLConnection->Params->Add("User_Name=usuario");
 SQLConnection->Params->Add("Password=clave");
 SQLConnection->Params->Add("FetchAll=True");
 SQLConnection->Params->Add("EnableBoolean=False");
 SQLConnection->VendorLib = "libmysql.dll";
 
 TSQLQuery *SQLQuery;
 SQLQuery=new TSQLQuery(NULL);

 SQLQuery->SQLConnection = SQLConnection; 
 
 //I need to now how many record returns this query:
 //     Select T2.id, T2.nombre 
 //     from capasperusu T1
 //     left join capasper T2 on (T2.id=T1.idCapa) 
 //     where T1.idUsuario=1
 //


 // CASE 1: THE PROBLEM
 // If we assign the query via Text property in one line, it crashes
 SQLQuery->SQL->Text=
   "select T2.id, T2.nombre "
   "from capasperusu T1 "
   "left join capasper T2 on (T2.id=T1.idCapa) "
   "where T1.idUsuario=1";
 
 SQLQuery->Open();
 Caption=SQLQuery->RecordCount; //CRASH!!!


 //CASE 2: Breaking the query in serveral lines 
 //             using Add method off SQL property
 //IN THIS CASE IT WORKS
   SQLQuery->SQL->Add("select T2.id, T2.nombre");
   SQLQuery->SQL->Add("from capasperusu T1");
   SQLQuery->SQL->Add("left join capasper T2 on (T2.id=T1.idCapa)");
   SQLQuery->SQL->Add("where T1.idUsuario=1");
   SQLQuery->Open();
   Caption=SQLQuery->RecordCount; //it works OK!!!
 
 //CASE 3: Breaking the query in serveral lines 
 //             using Delimiter and DelimitedText of SQL property
 SQLQuery->SQL->Delimiter=' ';
 SQLQuery->SQL->DelimitedText="select T2.id, T2.nombre "
   "from capasperusu T1 "
   "left join capasper T2 on (T2.id=T1.idCapa) "
   "where T1.idUsuario=1";
  }
 
   SQLQuery->Open();
   Caption=SQLQuery->RecordCount; //it works OK!!!