Non-blocking jsp

Hi,
I am using Java in order to create web application.
The application has to load a form which is sent it's data to a jsp that call a long business logic.
I need that the jsp will return a message like "thank you for using my service, an email will sent to you when the proccess is done."
The problem is that if I will write something like:
<html>
<head></head>
<body>
<span>thank you for using my service, an email will sent to you when the proccess is done</span>
<% businessClass.doLongOperation(); %>
</Body>
</html>
the jsp will run for long time and the user will have to wait for the operation to end. Moreover, i f the user will close the browser, I am not sure if the jsp will continue its job.
How can I isolate the long operation from the jsp so the user will not have to wait all the execution time and also how can I make the long operation execution not to be depend on the browser?
Naor

Fire a new thread and monitor the progress using HTTP refreshes or Ajaxical polls or just completely ignore it and let the user wait for mail.

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    reset(0);
    void reset(Type* handle)
    if(handle_)
    sword result;
    if((result = OCIHandleFree(
    handle_,
    TypeId)) != OCI_SUCCESS)
    assert(0);
    std::cerr << "Can't make OCIHandleFree" << std::endl;
    handle_ = handle;
    Type* get()
    return handle_;
    Type*& fill()
    reset(0);
    return handle_;
    private:
    Type* handle_;
    template<typename Type, unsigned long TypeId>
    class OCIDescriptorPtr
    public:
    OCIDescriptorPtr(): handle_(0) {}
    OCIDescriptorPtr(Type* handle): handle_(handle) {}
    ~OCIDescriptorPtr()
    reset(0);
    void reset(Type* handle)
    if(handle_)
    sword result;
    if((result = OCIDescriptorFree(
    handle_,
    TypeId)) != OCI_SUCCESS)
    std::cerr << "Can't make OCIDescriptorFree" << std::endl;
    handle_ = handle;
    Type* get()
    return handle_;
    Type*& fill()
    reset(0);
    return handle_;
    private:
    Type* handle_;
    void throw_oci_error(
    const char* fun,
    const char* oci_op,
    long status,
    OCIError* oci_error_handler,
    const char* query = 0)
    std::cerr << fun << ": can't make " << oci_op << ": status = " << status;
    if(status == OCI_SUCCESS_WITH_INFO ||
    status == OCI_ERROR)
    std::cerr << ", message = '";
    text err_buf[1024] = "";
    sb4 err_code = 0;
    OCIErrorGet(
    oci_error_handler,
    (ub4)1,
    0,
    &err_code,
    err_buf,
    sizeof(err_buf),
    (ub4)OCI_HTYPE_ERROR);
    std::cerr << err_buf << "', error code = " << err_code;
    exit(1);
    if(query)
    std::cerr << ", sql = " << query;
    OCIHandlePtr<OCIEnv, OCI_HTYPE_ENV> environment_handle;
    void connect(
    OCIEnv* environment_handle,
    const char* db,
    const char* user,
    const char* password,
    OCIHandlePtr<OCIError, OCI_HTYPE_ERROR>& error_handle,
    OCIHandlePtr<OCIServer, OCI_HTYPE_SERVER>& server_handle,
    OCIHandlePtr<OCISession, OCI_HTYPE_SESSION>& session_handle,
    OCIHandlePtr<OCISvcCtx, OCI_HTYPE_SVCCTX>& svc_context_handle)
    static const char* FUN = "connect()";
    sword result;
    // allocate an error handle
    if((result = OCIHandleAlloc(
    environment_handle,
    (void **) &error_handle.fill(),
    OCI_HTYPE_ERROR,
    0, // extra memory to allocate
    0)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIHandleAlloc", result, error_handle.get());
    // allocate a server handle
    if((result = OCIHandleAlloc(
    environment_handle,
    (void **) &server_handle.fill(),
    OCI_HTYPE_SERVER,
    0, // extra memory to allocate
    0)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIHandleAlloc", result, error_handle.get());
    if((result = OCIServerAttach(
    server_handle.get(),
    error_handle.get(),
    (text*)db,
    strlen(db),
    OCI_DEFAULT)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIServerAttach", result, error_handle.get());
    // allocate a service handle
    if((result = OCIHandleAlloc(
    environment_handle,
    (void **) &svc_context_handle.fill(),
    OCI_HTYPE_SVCCTX,
    0, // extra memory to allocate
    0)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIHandleAlloc", result, error_handle.get());
    // set the server attribute in the service context handle
    if((result = OCIAttrSet(
    svc_context_handle.get(),
    OCI_HTYPE_SVCCTX,
    server_handle.get(),
    sizeof(OCIServer*),
    OCI_ATTR_SERVER,
    error_handle.get())) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIHandleAlloc", result, error_handle.get());
    // allocate a user session handle
    if((result = OCIHandleAlloc(
    environment_handle,
    (void **)&session_handle.fill(),
    OCI_HTYPE_SESSION,
    0, // extra memory to allocate
    0)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIHandleAlloc", result, error_handle.get());
    // set username and password attributes in user session handle
    if((result = OCIAttrSet(
    session_handle.get(),
    OCI_HTYPE_SESSION,
    (text*)user,
    strlen(user),
    OCI_ATTR_USERNAME,
    error_handle.get())) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIAttrSet", result, error_handle.get());
    if((result = OCIAttrSet(
    session_handle.get(),
    OCI_HTYPE_SESSION,
    (text*)password,
    strlen(password),
    OCI_ATTR_PASSWORD,
    error_handle.get())) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIAttrSet", result, error_handle.get());
    // start the session
    if((result = OCISessionBegin(
    svc_context_handle.get(),
    error_handle.get(),
    session_handle.get(),
    OCI_CRED_RDBMS,
    OCI_DEFAULT)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCISessionBegin", result, error_handle.get());
    // set the user session attribute in the service context handle
    if((result = OCIAttrSet(
    svc_context_handle.get(),
    OCI_HTYPE_SVCCTX,
    session_handle.get(),
    sizeof(OCISession*),
    OCI_ATTR_SESSION,
    error_handle.get())) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIAttrSet", result, error_handle.get());
    ub1 attr_value = 1;
    if((result = OCIAttrSet(
    server_handle.get(),
    OCI_HTYPE_SERVER,
    &attr_value,
    sizeof(attr_value),
    OCI_ATTR_NONBLOCKING_MODE,
    error_handle.get())) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIAttrSet", result, error_handle.get());
    void disconnect(
    OCIEnv* environment_handle,
    OCIError* error_handle,
    OCIServer* server_handle,
    OCISession* session_handle,
    OCISvcCtx* svc_context_handle)
    static const char* FUN = "disconnect()";
    sword result;
    if((result = OCISessionEnd(
    svc_context_handle,
    error_handle,
    session_handle,
    OCI_DEFAULT)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCISessionEnd", result, error_handle);
    if((result = OCIServerDetach(
    server_handle,
    error_handle,
    OCI_DEFAULT)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIServerDetach", result, error_handle);
    OCILobLocator* FETCH_BUFFER_1[10000*1024];
    char IND_BUFFER_1[10000*1024];
    ub2 ERROR_BUFFER_1[1024];
    OCIDefine* define_handle_1;
    void clear_blob_buf(
    OCILobLocator** buf,
    unsigned long fetch_size)
    for(unsigned long i = 0; i < 1024; ++i)
    OCIDescriptorFree(
    buf,
    (ub4)OCI_DTYPE_LOB);
    ::memset(buf, 0, fetch_size * 1024);
    uint32_t RET_LEN4;
    sb4 oci_blob_callback(
    dvoid* ctx,
    OCIDefine* define,
    ub4 iter,
    dvoid** bufpp,
    ub4** alenpp,
    ub1* piecep,
    dvoid** indpp,
    ub2** rcodepp)
    RET_LEN4 = sizeof(OCILobLocator*);
    *bufpp = FETCH_BUFFER_1[iter];
    *alenpp = &RET_LEN4;
    *piecep = OCI_ONE_PIECE;
    *indpp = IND_BUFFER_1 + iter;
    *rcodepp = ERROR_BUFFER_1 + iter;
    //std::cout << "iter: " << iter << std::endl;
    return OCI_CONTINUE;
    int define_column(
    OCIEnv* environment_handle,
    OCISvcCtx* svc_handle,
    OCIStmt* stmt_handle,
    OCIError* error_handle,
    OCIDefine** define_handle,
    unsigned long pos,
    long oci_type,
    unsigned long fetch_size,
    OCILobLocator** buf,
    char* ind_buf,
    ub2* err_buf)
    static const char* FUN = "define_column()";
    sword result;
    if(oci_type == SQLT_BLOB)
    ::memset(buf, 0, fetch_size * 1024);
    for(int i = 0; i < 1024; ++i)
    if((result = OCIDescriptorAlloc(
    (dvoid*)environment_handle,
    (dvoid**)&buf[i],
    (ub4)OCI_DTYPE_LOB,
    (size_t)0,
    (dvoid**)0)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIDescriptorAlloc", result, error_handle);
    ub2 size = 0;
    OCIDescriptorPtr<OCIParam, OCI_DTYPE_PARAM> param_handle;
    // ub2 oci_data_type = 0;
    if((result = OCIParamGet(
    stmt_handle,
    OCI_HTYPE_STMT,
    error_handle,
    reinterpret_cast<void**>(&param_handle.fill()),
    pos)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIParamGet", result, error_handle);
    if((result = OCIAttrGet(
    param_handle.get(),
    OCI_DTYPE_PARAM,
    &size,
    0,
    OCI_ATTR_DATA_SIZE,
    error_handle)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIAttrGet", result, error_handle);
    if((result = OCIDefineByPos(
    stmt_handle,
    define_handle,
    error_handle,
    pos,
    # ifdef _DYN
    0,
    -1,
    #else
    buf,
    fetch_size,
    #endif
    oci_type,
    ind_buf,
    0,
    err_buf, // ptr to array of column-level return codes
    # ifdef _DYN
    OCI_DYNAMIC_FETCH
    # else
    OCI_DEFAULT
    # endif
    )) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIDefineByPos", result, error_handle);
    # ifdef _DYN
    if((result = OCIDefineDynamic(
    *define_handle,
    error_handle,
    0,
    oci_blob_callback)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIDefineByPos", result, error_handle);
    # endif
    return 0;
    int define_columns(
    OCIEnv* environment_handle,
    OCISvcCtx* svc_handle,
    OCIStmt* stmt_handle,
    OCIError* error_handle)
    static const char* FUN = "define_columns()";
    define_handle_1 = 0;
    int pos = 1;
    ::memset(ERROR_BUFFER_1, 0, 1024 * sizeof(ERROR_BUFFER_1[0]));
    define_column(
    environment_handle,
    svc_handle,
    stmt_handle,
    error_handle,
    &define_handle_1,
    pos++,
    SQLT_BLOB,
    sizeof(OCILobLocator*),
    FETCH_BUFFER_1,
    IND_BUFFER_1,
    ERROR_BUFFER_1);
    return 0;
    int execute_select(
    const char* db,
    const char* user,
    const char* password)
    static const char* FUN = "execute_select()";
    const unsigned long FETCH_COUNT = 1024;
    OCIHandlePtr<OCIError, OCI_HTYPE_ERROR> error_handle;
    OCIHandlePtr<OCIServer, OCI_HTYPE_SERVER> server_handle;
    OCIHandlePtr<OCISession, OCI_HTYPE_SESSION> session_handle;
    OCIHandlePtr<OCISvcCtx, OCI_HTYPE_SVCCTX> svc_context_handle;
    connect(
    environment_handle.get(),
    db,
    user,
    password,
    error_handle,
    server_handle,
    session_handle,
    svc_context_handle);
    OCIHandlePtr<OCIStmt, OCI_HTYPE_STMT> stmt_handle;
    sword result;
    if((result = OCIHandleAlloc(
    environment_handle.get(),
    (void**)&stmt_handle.fill(),
    OCI_HTYPE_STMT,
    0,
    0)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIHandleAlloc", result, error_handle.get());
    const char QUERY[] = "SELECT text FROM ADSERVERTEST_BLOB";
    ub4 rows = 0;
    if((result = OCIAttrSet(
    stmt_handle.get(),
    OCI_HTYPE_STMT,
    (dvoid *)&rows,
    (ub4)sizeof(ub4),
    OCI_ATTR_PREFETCH_ROWS,
    error_handle.get())) != OCI_SUCCESS)
    throw_oci_error(
    FUN, "OCIAttrSet(OCI_ATTR_PREFETCH_ROWS)", result, error_handle.get());
    if((result = OCIStmtPrepare(
    stmt_handle.get(),
    error_handle.get(),
    (text*)QUERY,
    strlen(QUERY),
    OCI_NTV_SYNTAX,
    OCI_DEFAULT)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIStmtPrepare", result, error_handle.get());
    ub2 stmt_type;
    if((result = OCIAttrGet(
    stmt_handle.get(),
    OCI_HTYPE_STMT,
    &stmt_type,
    0,
    OCI_ATTR_STMT_TYPE,
    error_handle.get())) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIAttrGet", result, error_handle.get());
    ub4 prev_fetched = 0;
    while((result = OCIStmtExecute(
    svc_context_handle.get(),
    stmt_handle.get(),
    error_handle.get(),
    0,
    0,
    0,
    0,
    OCI_DEFAULT)) != OCI_SUCCESS)
    if(result != OCI_STILL_EXECUTING)
    throw_oci_error(FUN, "OCIStmtExecute", result, error_handle.get());
    define_columns(
    environment_handle.get(),
    svc_context_handle.get(),
    stmt_handle.get(),
    error_handle.get());
    ub4 all_fetched_count = 0;
    while(true)
    while((result = OCIStmtFetch2(
    stmt_handle.get(),
    error_handle.get(),
    FETCH_COUNT,
    OCI_FETCH_NEXT,
    1,
    OCI_DEFAULT)) == OCI_STILL_EXECUTING
    # ifdef _DYN
    // || result == OCI_NEED_DATA
    # endif
    if (result != OCI_SUCCESS &&
    result != OCI_NO_DATA &&
    result != OCI_SUCCESS_WITH_INFO)
    std::cerr << FUN << ": can't make OCIStmtFetch2: status = " << result;
    std::cerr << ", message = '";
    text err_buf[1024] = "";
    sb4 err_code = 0;
    OCIErrorGet(
    error_handle.get(),
    (ub4)1,
    0,
    &err_code,
    err_buf,
    sizeof(err_buf),
    (ub4)OCI_HTYPE_ERROR);
    std::cerr << err_buf << "', error code = " << err_code << ", row errors: ";
    for(const ub2* cur = ERROR_BUFFER_1;
    cur < ERROR_BUFFER_1 + 1024; ++cur)
    if(*cur)
    std::cerr << "#" << (cur - ERROR_BUFFER_1) << ": " <<
    *cur << std::endl;
    ub4 fetched_count = 0;
    if((result = OCIAttrGet (
    stmt_handle.get(),
    OCI_HTYPE_STMT,
    &fetched_count,
    0,
    OCI_ATTR_ROW_COUNT,
    error_handle.get())) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIAttrGet", result, error_handle.get());
    all_fetched_count += fetched_count;
    if(fetched_count > 0)
    for(unsigned long i = 0; i < fetched_count - 1; ++i)
    ub4 lob_size;
    while((result = OCILobGetLength(
    svc_context_handle.get(),
    error_handle.get(),
    FETCH_BUFFER_1[i],
    &lob_size)) == OCI_STILL_EXECUTING)
    if(result != OCI_SUCCESS)
    throw_oci_error(FUN, "OCILobGetLength", result, error_handle.get());
    std::cout << "#" << i << ": ind = " << (unsigned long)IND_BUFFER_1[i] <<
    ", len = " << lob_size << std::endl;
    if(fetched_count - prev_fetched < FETCH_COUNT)
    break;
    prev_fetched = fetched_count;
    clear_blob_buf(
    FETCH_BUFFER_1,
    sizeof(OCILobLocator*));
    while((result = OCIStmtFetch(
    stmt_handle.get(),
    error_handle.get(),
    0,
    OCI_FETCH_NEXT,
    OCI_DEFAULT)) == OCI_STILL_EXECUTING
    disconnect(
    environment_handle.get(),
    error_handle.get(),
    server_handle.get(),
    session_handle.get(),
    svc_context_handle.get());
    return 0;
    int execute_update(
    const char* db,
    const char* user,
    const char* password)
    static const char* FUN = "execute_update()";
    OCIHandlePtr<OCIError, OCI_HTYPE_ERROR> error_handle;
    OCIHandlePtr<OCIServer, OCI_HTYPE_SERVER> server_handle;
    OCIHandlePtr<OCISession, OCI_HTYPE_SESSION> session_handle;
    OCIHandlePtr<OCISvcCtx, OCI_HTYPE_SVCCTX> svc_context_handle;
    connect(
    environment_handle.get(),
    db,
    user,
    password,
    error_handle,
    server_handle,
    session_handle,
    svc_context_handle);
    OCIHandlePtr<OCIStmt, OCI_HTYPE_STMT> stmt_handle;
    for(int i = 0; i < 1000; ++i)
    sword result;
    if((result = OCIHandleAlloc(
    environment_handle.get(),
    (void**)&stmt_handle.fill(),
    OCI_HTYPE_STMT,
    0,
    0)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIHandleAlloc", result, error_handle.get());
    std::ostringstream sql;
    std::string str;
    std::string et("\xEB\xB2\x88");
    unsigned long rep = ::rand() % 500 + 1;
    str.reserve(rep*et.size());
    for(unsigned long ei = 0; ei < rep; ++ei)
    str.append(et);
    sql << "BEGIN " <<
    "UPDATE ADSERVERTEST_BLOB SET text = "
    "utl_raw.cast_to_raw('" << str << "') "
    "WHERE id = " << i <<
    "END;";
    if((result = OCIStmtPrepare(
    stmt_handle.get(),
    error_handle.get(),
    (text*)sql.str().c_str(),
    sql.str().length(),
    OCI_NTV_SYNTAX,
    OCI_DEFAULT)) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIStmtPrepare", result, error_handle.get());
    while((result = OCIStmtExecute(
    svc_context_handle.get(),
    stmt_handle.get(),
    error_handle.get(),
    1,
    0,
    0,
    0,
    OCI_DEFAULT)) != OCI_SUCCESS)
    if(result != OCI_STILL_EXECUTING)
    throw_oci_error(FUN, "OCIStmtExecute", result, error_handle.get());
    disconnect(
    environment_handle.get(),
    error_handle.get(),
    server_handle.get(),
    session_handle.get(),
    svc_context_handle.get());
    return 0;
    void* select_thread(void* ctx)
    while(true)
    execute_select(
    "//oraclept.ocslab.com/addbpt.ocslab.com",
    "bs_unittest_4",
    "adserver");
    // std::cout << "select finished" << std::endl;
    return ctx;
    void* update_thread(void* ctx)
    while(true)
    execute_update(
    "//oraclept.ocslab.com/addbpt.ocslab.com",
    "bs_unittest_4",
    "adserver");
    // std::cout << "update finished" << std::endl;
    return ctx;
    int main()
    static const char* FUN = "main()";
    sword result;
    // allocate an environment handle
    if((result = OCIEnvCreate(
    &environment_handle.fill(),
    OCI_OBJECT | OCI_THREADED,
    0, // context
    0, // malloc
    0, // realloc
    0, // free
    0, // extra memory to allocate
    0) // pointer to user-memory
    ) != OCI_SUCCESS)
    throw_oci_error(FUN, "OCIEnvCreate", result, 0);
    pthread_t th1, th2;
    pthread_create(&th1, 0, select_thread, 0);
    pthread_create(&th2, 0, update_thread, 0);
    pthread_join(th1, 0);
    pthread_join(th2, 0);
    return 0;
    Edited by: user13011391 on 20.04.2010 5:50
    Edited by: user13011391 on 20.04.2010 6:00
    Edited by: user13011391 on 20.04.2010 6:15

    Hi all.
    I have problem:
    I try select BLOB field into OCILobLocator* buffer in Non Blocking mode, and receive 'ORA-03106: fatal two-task communication protocol error' sometimes.
    Details:
    Application contains two threads : 1. select blob field, 2. update it.
    I tried separate update and select to different apps (and run its in one time) - problem reproduced.
    problem reproduced for OCIStmtFetch and OCIStmtFetch2.
    If disable non blocking mode - problem disappear.
    if error appear - record level error code contains 1405. Need wait few minutes for error message appearing (~1 minute in my case).
    Using of OCI_DEFAULT in OCIDefineByPos instead OCI_DYNAMIC_FETCH don't solve problem.
    I use oracle server and client library with version 10.2.0.4
    Output sample:
    execute_select(): can't make OCIStmtFetch2: status = -1, message = 'ORA-03106: fatal two-task communication protocol error
    ', error code = 3106, row errors: #877: 1405
    execute_select(): can't make OCIStmtFetch2: status = -1, message = 'ORA-03106: fatal two-task communication protocol error
    ', error code = 3106, row errors: #54: 1405
    execute_select(): can't make OCIStmtFetch2: status = -1, message = 'ORA-03106: fatal two-task communication protocol error
    ', error code = 3106, row errors: #877: 1405
    execute_select(): can't make OCIStmtFetch2: status = -1, message = 'ORA-03106: fatal two-task communication protocol error
    ', error code = 3106, row errors: #54: 1405
    Can anybody help me ?
    m.b. exists workaround ?
    #include <iostream>
    #include <sstream>
    #include <assert.h>
    #include <oci.h>
    #define _DYN 1
    before run this test run next sql at DB:
    CREATE TABLE ADSERVERTEST_BLOB(id NUMBER(10), text BLOB);
    BEGIN
    FOR i IN 0..999 LOOP
    INSERT INTO ADSERVERTEST_BLOB(id, text) VALUES(i, utl_raw.cast_to_raw('init'));
    END LOOP;
    END;
    template<typename Type, unsigned long TypeId>
    class OCIHandlePtr
    public:
    OCIHandlePtr(): handle_(0) {}
    OCIHandlePtr(Type* handle): handle_(handle) {}
    ~OCIHandlePtr()
    reset(0);
    void reset(Type* handle)
    if(handle_)
    sword result;
    if((result = OCIHandleFree(
    handle_,
    TypeId)) != OCI_SUCCESS)
    assert(0);
    std::cerr << "Can't make OCIHandleFree" << std::endl;
    handle_ = handle;
    Type* get()
    return handle_;
    Type*& fill()
    reset(0);
    return handle_;
    private:
    Type* handle_;
    template<typename Type, unsigned long TypeId>
    class OCIDescriptorPtr
    public:
    OCIDescriptorPtr(): handle_(0) {}
    OCIDescriptorPtr(Type* handle): handle_(handle) {}
    ~OCIDescriptorPtr()
    reset(0);
    void reset(Type* handle)
    if(handle_)
    sword result;
    if((result = OCIDescriptorFree(
    handle_,
    TypeId)) != OCI_SUCCESS)
    std::cerr << "Can't make OCIDescriptorFree" << std::endl;
    handle_ = handle;
    Type* get()
    return handle_;
    Type*& fill()
    reset(0);
    return handle_;
    private:
    Type* handle_;
    void throw_oci_error(
    const char* fun,
    const char* oci_op,
    long status,
    OCIError* oci_error_handler,
    const char* query = 0)
    std::cerr << fun << ": can't make " << oci_op << ": status = " << status;
    if(status == OCI_SUCCESS_WITH_INFO ||
    status == OCI_ERROR)
    std::cerr << ", message = '";
    text err_buf[1024] = "";
    sb4 err_code = 0;
    OCIErrorGet(
    oci_error_handler,
    (ub4)1,
    0,
    &err_code,
    err_buf,
    sizeof(err_buf),
    (ub4)OCI_HTYPE_ERROR);
    std::cerr << err_buf << "', error code = " << err_code;
    exit(1);
    if(query)
    std::cerr << ", sql = " << query;
    OCIHandlePtr<OCIEnv, OCI_HTYPE_ENV> environment_handle;
    void connect(
    OCIEnv* environment_handle,
    const char* db,
    const char* user,
    const char* password,
    OCIHandlePtr<OCIError, OCI_HTYPE_ERROR>& error_handle,
    OCIHandlePtr<OCIServer, OCI_HTYPE_SERVER>& server_handle,
    OCIHandlePtr<OCISession, OCI_HTYPE_SESSION>& session_handle,
    OCIHandlePtr<OCISvcCtx, OCI_HTYPE_SVCCTX>& svc_context_handle)
    static const char* FUN = "connect()";
    sword result;
    // allocate an error handle
    if((result = OCIHandleAlloc(
    environment_handle,
    (void **) &error_handle.fill(),
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    OCIError* error_handle,
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    unsigned long pos,
    long oci_type,
    unsigned long fetch_size,
    OCILobLocator** buf,
    char* ind_buf,
    ub2* err_buf)
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    0,
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    Edited by: user13011391 on 20.04.2010 5:50
    Edited by: user13011391 on 20.04.2010 6:00
    Edited by: user13011391 on 20.04.2010 6:15

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