C / C++ / MFC

FirstPrevNext

SQLFetchScroll on Asynchronous Statements (CRecordset/SQL API) Tom Tempelaere aka TiTi19-Oct-01 0:16 Tom Tempelaere aka TiTi 19-Oct-01 0:16  Hi, I have a strange problem using SQL API from Visual C++ 6. I'm not working directly with the SQL API , instead I'm using MFC CRecordset and CDatabase. Of course, I had to subclass these to modify general behaviour (and , what a task!). One of the (many) things that CRecordset doesn't support is asynchronous query processing. And that's where I have a strange problem that I can't find a solution for. After allocating the statement (::SQLAllocStmt) and setting the option for asynchronous processing (::SQLSetStmtOption(m_hstmt, SQL_ASYNC_ENABLE, SQL_ASYNC_ENABLE_ON)) the query is executed (::SQLExecDirect(m_hstmt, query_nts_string, SQL_NTS)). This last SQL function returns SQL_STILL_EXECUTING as long as the query isn't finished. The SQL documentation states that when processing asynchronously, only the same SQL function with the same arguments or SQLCancel or some other diagnostic functions can be called on the statement, as long as the original SQL function is still executing (check MSDN). I modified CRecordset (Visual C++) through subclassing to support asynchronous processing using these rules. I added a method IsStillExecuting to check whether the query is still executing, and a method CancelQuery which cancels the query if it is still executing (CRecordset's method Cancel doesn't work). These methods work fine following the rules I mentioned. Also, reading the records from the resultset (recordset) works fine, *but*, only for the first number of rows (around 20). The records in CRecordset are read using SQLExtendedFetch, but I modified this in my subclass to use SQLFetchScroll because I read in SQL docu that SQLExtendedFetch cannot be used on asynchronous statements. After some number of rows the SQLFetchScroll function returns SQL_STILL_EXECUTING. Ok , I thought, I'll just have to call SQLFetchScroll until it no longer returns SQL_STILL_EXECUTING, but that does *not* work , contrary to what the SQL API docu states. The second time SQLFetchScroll is called it returns -1 (an error code). The exception that is thrown states "HY010 Function sequence error". I checked SQL API docu and didn't find why this is happening. The statement is processed from one thread only, no other SQL functions are executed on the statement when it is still executing, and I didn't mix SQLExtendedFetch calls with SQLFetchScroll calls. So what can I be doing wrong? Tnx PS: OS specifics are: NT4/SP5, Visual C++6SP4(?), ODBC driver for MS SQL Server version: 3.70.08.20 (SQLSRV32.DLL). TiTi (Tom Tempelaere) Upsilon S.A. - Financial and Computer Engineering Luxembourg chtmlview man~o18-Oct-01 23:46 man~o 18-Oct-01 23:46  - first i use navigate2 to load a web page - then i want to fill in an edit box and then to press a submit button (of course i dont want to do it manually, but code pls) Re: chtmlview Bret Faller19-Oct-01 7:02 Bret Faller 19-Oct-01 7:02  You need to get a pointer the the IHTMLDocument2 interface which can be done like so: IDispatch* pDisp = GetHtmlDocument(); IHTMLDocument2* pDoc = NULL; pDisp->QueryInterface(IID_IHTMLDocument2, (void**)&pDoc); IHTMLElementCollection* pColl = NULL; pDoc->get_forms(&pColl); Then you can browse through all the objects on the form (document) by using the methods of the IHTMLElementCollection interface. Hope this helps. Bret Faller Odyssey Computing, Inc. Window styles 18-Oct-01 23:07 18-Oct-01 23:07  I would Like to create a window that essentially looks like a toolbar but is independent can any one help how to do it thanks in advance Re: Window styles Nish Nishant18-Oct-01 23:52 Nish Nishant 18-Oct-01 23:52  you could try using the WS_EX_TOOLWINDOW style Nish ATL again mimi18-Oct-01 23:06 mimi 18-Oct-01 23:06  I try now to convert all my project (that I writed as MFC dll) to ATL type I opened by the wizars ATL class Dialog with mfc support and I fill its method with my code that I copies from my project. Maybe someone can tell me if is it possible that the ATL will contain code of MFC as mfc functions , types and objects like CString. I trys it and this is works with mfc client program but the question if is it will be match for Delphi and another . What do you say ? With manny thanks !!! video for windows Jimolo18-Oct-01 22:53 Jimolo 18-Oct-01 22:53  hi, i want to capture pix from cam. in win98. i am using quickcam's activeX componment. however, it is really a bad ocx. it will crashed in a k6-300 but work perfect in my p3-800. since, i need to deploy my program in a embedded pc. so, i need to find other solution. did anyone has such experience? anyone try to capture a picture start with video for windows? thanks, jim reply me 18-Oct-01 21:35 18-Oct-01 21:35  Does anybody know how to accomplish this?when i use dumpbin like dumpbin /exports gcmail.dll iam getting problem like gcmail.dll ia an ne format ,use exehdr to dump it. chands reply me 18-Oct-01 21:34 18-Oct-01 21:34  Can anyone help me? I need to extract information about functions in a dll. Does anybody know how to accomplish this?when i use dumpbin like dumpbin /exports gcmail.dll iam getting problem like gcmail.dll ia an ne format ,use exehdr to dump it. chands Re: reply me Joan M19-Oct-01 6:27 Joan M 19-Oct-01 6:27  I don't know in wich version was the "dependency walker" included, but in the VC++6 there's that app. it can help you (I think). There you can load the DLL and look for information related to it. I'm novice, I expect to help you... I was trying them... (just kidding...) CreateWaitableTimer is not creating Joe Moldovan18-Oct-01 21:27 Joe Moldovan 18-Oct-01 21:27  I run VS6(SP5) on Win2000(SR2). I have a one line program which will not compile. #include windows.h int APIENTRY WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance,LPSTR lpCmdLine, int nCmdShow ) { CreateWaitableTimer( NULL, TRUE, "JOE" ); return 0; } c:\develop\test\test.cpp(8) : error C2065: 'CreateWaitableTimer' : undeclared identifier To clarify the situation, I have no precompiled headers. The call definition is seen by VS because a mouse hover over the source shows the call prototype correctly. If I change windows.h to afxwin.h I get a good compile. QUESTION: Why can't I compile with windows.h? What has a Win32 API call got to do with MFC - or rather what does afxwin.h do that I don't? Thanks for any advice ! Re: CreateWaitableTimer is not creating Joe Moldovan18-Oct-01 21:30 Joe Moldovan 18-Oct-01 21:30  Forgot to mention: The MSDN example fails to compile also. Re: CreateWaitableTimer is not creating Michael Dunn18-Oct-01 22:19 Michael Dunn 18-Oct-01 22:19  Your question is answered in the VC forum FAQ. --Mike-- http://home.inreach.com/mdunn/ "....." -- Silent Bob your with and Re: CreateWaitableTimer is not creating Joe Moldovan18-Oct-01 23:14 Joe Moldovan 18-Oct-01 23:14  Thanks Michael!!! Saved me again as usual. I also found the answer in MSDN Q184796 together with an example. Are there any web sites about "AI"? Maer72718-Oct-01 21:24 Maer727 18-Oct-01 21:24  Are there any web sites about "AI(Artificial Intelligence)"? Thanks, Maer Re: Are there any web sites about "AI"? Nish Nishant18-Oct-01 23:55 Nish Nishant 18-Oct-01 23:55  try searching on google Nish Re: Are there any web sites about "AI"? 19-Oct-01 2:25 19-Oct-01 2:25  You might take a look at www.gamedev.net regards Re: Are there any web sites about "AI"? Carlos Antollini19-Oct-01 12:42 Carlos Antollini 19-Oct-01 12:42  http://cs.felk.cvut.cz/~xobitko/ga/ Enjoy it.... Nice weekend Carlos Antollini. Today is Friday.... SSShhh Bob!!! Re: Are there any web sites about "AI"? Maer72720-Oct-01 3:24 Maer727 20-Oct-01 3:24  Hi, Antollini! It is a nice site! Regards, Maer about Dll loading order Maer72718-Oct-01 21:19 Maer727 18-Oct-01 21:19  What means "dependency loops in the DLL load order"? (from MSDN "DllMain") Can you show me an example? Thanks, Maer About "CEdit" Maer72718-Oct-01 21:11 Maer727 18-Oct-01 21:11  How to precisely create a CEdit that contains 6 rows with 10 characters in a row? (the font and size of the characters are not certain, so we must get the width and height of the font, but I do not know how to do that) Can you show me an example? Thanks, Maer Re: About "CEdit" Christian Graus18-Oct-01 22:28 Christian Graus 18-Oct-01 22:28  You need to make the CEdit multiline, you need to get the size of the font, and then you need to call MoveWindow or SetWindowPos to size the CEdit accordingly. You probably have to take into account the edge of the CEdit also. Christian As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet. Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery. Re: About "CEdit" Maer72720-Oct-01 3:12 Maer727 20-Oct-01 3:12  Thanks pal! Your answer is the one I am looking for. Have a nice day! Maer a thread local storage (TLS) index Maer72718-Oct-01 21:00 Maer727 18-Oct-01 21:00  What is the function of "a thread local storage (TLS) index"? What is the difference between it and an ordinary parameter? Can you help? Thanks, Maer Re: a thread local storage (TLS) index Steen Krogsgaard18-Oct-01 22:48 Steen Krogsgaard 18-Oct-01 22:48  The thread local storage (TLS) is a place provided by Win32 where you can put thread-specific data. Imagine you have a multi-threaded program, and you have some piece of data in each thread which is specific for that thread. Win32 gives you the TLS to store this kind of thread data. The index-part is because you can allocate many TLS "slots". To answer what's the difference between a TLS index and an ordinary parameter I'd have to know your context. Cheers Steen. "To claim that computer games influence children is rediculous. If Pacman had influenced children born in the 80'ies we would see a lot of youngsters running around in dark rooms eating pills while listening to monotonous music"

Last Visit: 31-Dec-99 18:00     Last Update: 3-Jul-24 10:35 Refresh ᐊ Prev1...17870178711787217873178741787517876178771787817879 Next ᐅ

General    News    Suggestion    Question    Bug    Answer    Joke    Praise    Rant    Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.