QODBCResult Class Reference

#include <qsql_odbc.h>

Inheritance diagram for QODBCResult:

Public Functions
bool	exec ()
	Executes the query, returning true if successful; otherwise returns false. More...
QVariant	handle () const
	Returns the low-level database handle for this result set wrapped in a QVariant or an invalid QVariant if there is no handle. More...
bool	prepare (const QString &query)
	Prepares the given query for execution; the query will normally use placeholders so that it can be executed repeatedly. More...
	QODBCResult (const QODBCDriver *db, QODBCDriverPrivate *p)
virtual void	setForwardOnly (bool forward)
	Sets forward only mode to forward. More...
virtual	~QODBCResult ()
Public Functions inherited from QSqlResult
virtual	~QSqlResult ()
	Destroys the object and frees any allocated resources. More...

Protected Functions
QVariant	data (int field)
	Returns the data for field index in the current row as a QVariant. More...
bool	fetch (int i)
	Positions the result to an arbitrary (zero-based) row index. More...
bool	fetchFirst ()
	Positions the result to the first record (row 0) in the result. More...
bool	fetchLast ()
	Positions the result to the last record (last row) in the result. More...
bool	fetchNext ()
	Positions the result to the next available record (row) in the result. More...
bool	fetchPrevious ()
	Positions the result to the previous record (row) in the result. More...
bool	isNull (int field)
	Returns true if the field at position index in the current row is null; otherwise returns false. More...
bool	nextResult ()
int	numRowsAffected ()
	Returns the number of rows affected by the last query executed, or -1 if it cannot be determined or if the query is a SELECT statement. More...
QSqlRecord	record () const
	Returns the current record if the query is active; otherwise returns an empty QSqlRecord. More...
bool	reset (const QString &query)
	Sets the result to use the SQL statement query for subsequent data retrieval. More...
int	size ()
	Returns the size of the SELECT result, or -1 if it cannot be determined or if the query is not a SELECT statement. More...
void	virtual_hook (int id, void *data)
Protected Functions inherited from QSqlResult
void	addBindValue (const QVariant &val, QSql::ParamType type)
	Binds the value val of parameter type paramType to the next available position in the current record (row). More...
int	at () const
	Returns the current (zero-based) row position of the result. More...
BindingSyntax	bindingSyntax () const
	Returns the binding syntax used by prepared queries. More...
virtual void	bindValue (int pos, const QVariant &val, QSql::ParamType type)
	Binds the value val of parameter type paramType to position index in the current record (row). More...
virtual void	bindValue (const QString &placeholder, const QVariant &val, QSql::ParamType type)
	Binds the value val of parameter type paramType to the placeholder name in the current record (row). More...
QSql::ParamType	bindValueType (const QString &placeholder) const
	Returns the parameter type for the value bound with the given placeholder name. More...
QSql::ParamType	bindValueType (int pos) const
	Returns the parameter type for the value bound at position index. More...
QVariant	boundValue (const QString &placeholder) const
	Returns the value bound by the given placeholder name in the current record (row). More...
QVariant	boundValue (int pos) const
	Returns the value bound at position index in the current record (row). More...
int	boundValueCount () const
	Returns the number of bound values in the result. More...
QString	boundValueName (int pos) const
	Returns the name of the bound value at position index in the current record (row). More...
QVector< QVariant > &	boundValues () const
	Returns a vector of the result's bound values for the current record (row). More...
void	clear ()
	Clears the entire result set and releases any associated resources. More...
void	detachFromResultSet ()
const QSqlDriver *	driver () const
	Returns the driver associated with the result. More...
bool	execBatch (bool arrayBind=false)
	Executes a prepared query in batch mode if the driver supports it, otherwise emulates a batch execution using bindValue() and exec(). More...
QString	executedQuery () const
	Returns the query that was actually executed. More...
bool	hasOutValues () const
	Returns true if at least one of the query's bound values is a QSql::Out or a QSql::InOut; otherwise returns false. More...
bool	isActive () const
	Returns true if the result has records to be retrieved; otherwise returns false. More...
bool	isForwardOnly () const
	Returns true if you can only scroll forward through the result set; otherwise returns false. More...
bool	isSelect () const
	Returns true if the current result is from a SELECT statement; otherwise returns false. More...
bool	isValid () const
	Returns true if the result is positioned on a valid record (that is, the result is not positioned before the first or after the last record); otherwise returns false. More...
QSqlError	lastError () const
	Returns the last error associated with the result. More...
virtual QVariant	lastInsertId () const
	Returns the object ID of the most recent inserted row if the database supports it. More...
QString	lastQuery () const
	Returns the current SQL query text, or an empty string if there isn't one. More...
bool	nextResult ()
QSql::NumericalPrecisionPolicy	numericalPrecisionPolicy () const
	QSqlResult (const QSqlDriver *db)
	Creates a QSqlResult using database driver db. More...
virtual bool	savePrepare (const QString &sqlquery)
	Prepares the given query, using the underlying database functionality where possible. More...
virtual void	setActive (bool a)
	This function is provided for derived classes to set the internal active state to active. More...
virtual void	setAt (int at)
	This function is provided for derived classes to set the internal (zero-based) row position to index. More...
virtual void	setLastError (const QSqlError &e)
	This function is provided for derived classes to set the last error to error. More...
void	setNumericalPrecisionPolicy (QSql::NumericalPrecisionPolicy policy)
virtual void	setQuery (const QString &query)
	Sets the current query for the result to query. More...
virtual void	setSelect (bool s)
	This function is provided for derived classes to indicate whether or not the current statement is a SQL SELECT statement. More...

Properties
QODBCPrivate *	d

Additional Inherited Members
Protected Types inherited from QSqlResult
enum	BindingSyntax { PositionalBinding, NamedBinding }
	This enum type specifies the different syntaxes for specifying placeholders in prepared queries. More...
enum	VirtualHookOperation { BatchOperation, DetachFromResultSet, SetNumericalPrecision, NextResult }

Detailed Description

Definition at line 82 of file qsql_odbc.h.

Constructors and Destructors

QODBCResult()

QODBCResult::QODBCResult	(	const QODBCDriver *	db,
		QODBCDriverPrivate *	p
	)

Definition at line 889 of file qsql_odbc.cpp.

: QSqlResult(db)
{
    d = new QODBCPrivate(p);
}

~QODBCResult()

QODBCResult::~QODBCResult ( )

virtual

Definition at line 895 of file qsql_odbc.cpp.

{
    if (d->hStmt && d->isStmtHandleValid(driver()) && driver()->isOpen()) {
        SQLRETURN r = SQLFreeHandle(SQL_HANDLE_STMT, d->hStmt);
        if (r != SQL_SUCCESS)
            qSqlWarning(QLatin1String("QODBCDriver: Unable to free statement handle ")
                         + QString::number(r), d);
    }

    delete d;
}

Functions

data()

QVariant QODBCResult::data ( int  index )

protectedvirtual

Returns the data for field index in the current row as a QVariant.

This function is only called if the result is in an active state and is positioned on a valid record and index is non-negative. Derived classes must reimplement this function and return the value of field index, or QVariant() if it cannot be determined.

Implements QSqlResult.

Definition at line 1128 of file qsql_odbc.cpp.

Referenced by isNull(), prepare(), reset(), and virtual_hook().

{
    if (field >= d->rInf.count() || field < 0) {
        qWarning() << "QODBCResult::data: column" << field << "out of range";
        return QVariant();
    }
    if (field < d->fieldCacheIdx)
        return d->fieldCache.at(field);

    SQLRETURN r(0);
    SQLLEN lengthIndicator = 0;

    for (int i = d->fieldCacheIdx; i <= field; ++i) {
        // some servers do not support fetching column n after we already
        // fetched column n+1, so cache all previous columns here
        const QSqlField info = d->rInf.field(i);
        switch (info.type()) {
        case QVariant::LongLong:
            d->fieldCache[i] = qGetBigIntData(d->hStmt, i);
        break;
        case QVariant::ULongLong:
            d->fieldCache[i] = qGetBigIntData(d->hStmt, i, false);
            break;
        case QVariant::Int:
            d->fieldCache[i] = qGetIntData(d->hStmt, i);
        break;
        case QVariant::UInt:
            d->fieldCache[i] = qGetIntData(d->hStmt, i, false);
            break;
        case QVariant::Date:
            DATE_STRUCT dbuf;
            r = SQLGetData(d->hStmt,
                            i + 1,
                            SQL_C_DATE,
                            (SQLPOINTER)&dbuf,
                            0,
                            &lengthIndicator);
            if ((r == SQL_SUCCESS || r == SQL_SUCCESS_WITH_INFO) && (lengthIndicator != SQL_NULL_DATA))
                d->fieldCache[i] = QVariant(QDate(dbuf.year, dbuf.month, dbuf.day));
            else
                d->fieldCache[i] = QVariant(QVariant::Date);
        break;
        case QVariant::Time:
            TIME_STRUCT tbuf;
            r = SQLGetData(d->hStmt,
                            i + 1,
                            SQL_C_TIME,
                            (SQLPOINTER)&tbuf,
                            0,
                            &lengthIndicator);
            if ((r == SQL_SUCCESS || r == SQL_SUCCESS_WITH_INFO) && (lengthIndicator != SQL_NULL_DATA))
                d->fieldCache[i] = QVariant(QTime(tbuf.hour, tbuf.minute, tbuf.second));
            else
                d->fieldCache[i] = QVariant(QVariant::Time);
        break;
        case QVariant::DateTime:
            TIMESTAMP_STRUCT dtbuf;
            r = SQLGetData(d->hStmt,
                            i + 1,
                            SQL_C_TIMESTAMP,
                            (SQLPOINTER)&dtbuf,
                            0,
                            &lengthIndicator);
            if ((r == SQL_SUCCESS || r == SQL_SUCCESS_WITH_INFO) && (lengthIndicator != SQL_NULL_DATA))
                d->fieldCache[i] = QVariant(QDateTime(QDate(dtbuf.year, dtbuf.month, dtbuf.day),
                       QTime(dtbuf.hour, dtbuf.minute, dtbuf.second, dtbuf.fraction / 1000000)));
            else
                d->fieldCache[i] = QVariant(QVariant::DateTime);
            break;
        case QVariant::ByteArray:
            d->fieldCache[i] = qGetBinaryData(d->hStmt, i);
            break;
        case QVariant::String:
            d->fieldCache[i] = qGetStringData(d->hStmt, i, info.length(), d->unicode);
            break;
        case QVariant::Double:
            switch(numericalPrecisionPolicy()) {
                case QSql::LowPrecisionInt32:
                    d->fieldCache[i] = qGetIntData(d->hStmt, i);
                    break;
                case QSql::LowPrecisionInt64:
                    d->fieldCache[i] = qGetBigIntData(d->hStmt, i);
                    break;
                case QSql::LowPrecisionDouble:
                    d->fieldCache[i] = qGetDoubleData(d->hStmt, i);
                    break;
                case QSql::HighPrecision:
                    d->fieldCache[i] = qGetStringData(d->hStmt, i, info.length(), false);
                    break;
            }
            break;
        default:
            d->fieldCache[i] = QVariant(qGetStringData(d->hStmt, i, info.length(), false));
            break;
        }
        d->fieldCacheIdx = field + 1;
    }
    return d->fieldCache[field];
}

exec()

bool QODBCResult::exec ( )

virtual

Executes the query, returning true if successful; otherwise returns false.

See also

prepare()

Reimplemented from QSqlResult.

Definition at line 1318 of file qsql_odbc.cpp.

{
    setActive(false);
    setAt(QSql::BeforeFirstRow);
    d->rInf.clear();
    d->fieldCache.clear();
    d->fieldCacheIdx = 0;

    if (!d->hStmt) {
        qSqlWarning(QLatin1String("QODBCResult::exec: No statement handle available"), d);
        return false;
    }

    if (isSelect())
        SQLCloseCursor(d->hStmt);

    QVector<QVariant>& values = boundValues();
    QVector<QByteArray> tmpStorage(values.count(), QByteArray()); // holds temporary buffers
    QVarLengthArray<SQLLEN, 32> indicators(values.count());
    memset(indicators.data(), 0, indicators.size() * sizeof(SQLLEN));

    // bind parameters - only positional binding allowed
    int i;
    SQLRETURN r;
    for (i = 0; i < values.count(); ++i) {
        if (bindValueType(i) & QSql::Out)
            values[i].detach();
        const QVariant &val = values.at(i);
        SQLLEN *ind = &indicators[i];
        if (val.isNull())
            *ind = SQL_NULL_DATA;
        switch (val.type()) {
            case QVariant::Date: {
                QByteArray &ba = tmpStorage[i];
                ba.resize(sizeof(DATE_STRUCT));
                DATE_STRUCT *dt = (DATE_STRUCT *)ba.constData();
                QDate qdt = val.toDate();
                dt->year = qdt.year();
                dt->month = qdt.month();
                dt->day = qdt.day();
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_DATE,
                                      SQL_DATE,
                                      0,
                                      0,
                                      (void *) dt,
                                      0,
                                      *ind == SQL_NULL_DATA ? ind : NULL);
                break; }
            case QVariant::Time: {
                QByteArray &ba = tmpStorage[i];
                ba.resize(sizeof(TIME_STRUCT));
                TIME_STRUCT *dt = (TIME_STRUCT *)ba.constData();
                QTime qdt = val.toTime();
                dt->hour = qdt.hour();
                dt->minute = qdt.minute();
                dt->second = qdt.second();
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_TIME,
                                      SQL_TIME,
                                      0,
                                      0,
                                      (void *) dt,
                                      0,
                                      *ind == SQL_NULL_DATA ? ind : NULL);
                break; }
            case QVariant::DateTime: {
                QByteArray &ba = tmpStorage[i];
                ba.resize(sizeof(TIMESTAMP_STRUCT));
                TIMESTAMP_STRUCT * dt = (TIMESTAMP_STRUCT *)ba.constData();
                QDateTime qdt = val.toDateTime();
                dt->year = qdt.date().year();
                dt->month = qdt.date().month();
                dt->day = qdt.date().day();
                dt->hour = qdt.time().hour();
                dt->minute = qdt.time().minute();
                dt->second = qdt.time().second();

                int precision = d->driverPrivate->datetime_precision - 20; // (20 includes a separating period)
                if (precision <= 0) {
                    dt->fraction = 0;
                } else {
                    dt->fraction = qdt.time().msec() * 1000000;

                    // (How many leading digits do we want to keep?  With SQL Server 2005, this should be 3: 123000000)
                    int keep = (int)qPow(10.0, 9 - qMin(9, precision));
                    dt->fraction = (dt->fraction / keep) * keep;
                }

                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_TIMESTAMP,
                                      SQL_TIMESTAMP,
                                      d->driverPrivate->datetime_precision,
                                      precision,
                                      (void *) dt,
                                      0,
                                      *ind == SQL_NULL_DATA ? ind : NULL);
                break; }
            case QVariant::Int:
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_SLONG,
                                      SQL_INTEGER,
                                      0,
                                      0,
                                      (void *) val.constData(),
                                      0,
                                      *ind == SQL_NULL_DATA ? ind : NULL);
                break;
            case QVariant::UInt:
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_ULONG,
                                      SQL_NUMERIC,
                                      15,
                                      0,
                                      (void *) val.constData(),
                                      0,
                                      *ind == SQL_NULL_DATA ? ind : NULL);
                break;
            case QVariant::Double:
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_DOUBLE,
                                      SQL_DOUBLE,
                                      0,
                                      0,
                                      (void *) val.constData(),
                                      0,
                                      *ind == SQL_NULL_DATA ? ind : NULL);
                break;
            case QVariant::LongLong:
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_SBIGINT,
                                      SQL_BIGINT,
                                      0,
                                      0,
                                      (void *) val.constData(),
                                      0,
                                      *ind == SQL_NULL_DATA ? ind : NULL);
                break;
            case QVariant::ULongLong:
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_UBIGINT,
                                      SQL_BIGINT,
                                      0,
                                      0,
                                      (void *) val.constData(),
                                      0,
                                      *ind == SQL_NULL_DATA ? ind : NULL);
                break;
            case QVariant::ByteArray:
                if (*ind != SQL_NULL_DATA) {
                    *ind = val.toByteArray().size();
                }
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_BINARY,
                                      SQL_LONGVARBINARY,
                                      val.toByteArray().size(),
                                      0,
                                      (void *) val.toByteArray().constData(),
                                      val.toByteArray().size(),
                                      ind);
                break;
            case QVariant::Bool:
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_BIT,
                                      SQL_BIT,
                                      0,
                                      0,
                                      (void *) val.constData(),
                                      0,
                                      *ind == SQL_NULL_DATA ? ind : NULL);
                break;
            case QVariant::String:
                if (d->unicode) {
                    QByteArray &ba = tmpStorage[i];
                    QString str = val.toString();
                    if (*ind != SQL_NULL_DATA)
                        *ind = str.length() * sizeof(SQLTCHAR);
                    int strSize = str.length() * sizeof(SQLTCHAR);

                    if (bindValueType(i) & QSql::Out) {
                        QVarLengthArray<SQLTCHAR> a(toSQLTCHAR(str));
                        a.reserve(str.capacity());
                        r = SQLBindParameter(d->hStmt,
                                            i + 1,
                                            qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                            SQL_C_TCHAR,
                                            strSize > 254 ? SQL_WLONGVARCHAR : SQL_WVARCHAR,
                                            0, // god knows... don't change this!
                                            0,
                                            (void *)a.constData(),
                                            a.size(),
                                            ind);
                        break;
                    }
                    ba = QByteArray((const char *)toSQLTCHAR(str).constData(), str.size()*sizeof(SQLTCHAR));
                    r = SQLBindParameter(d->hStmt,
                                          i + 1,
                                          qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                          SQL_C_TCHAR,
                                          strSize > 254 ? SQL_WLONGVARCHAR : SQL_WVARCHAR,
                                          strSize,
                                          0,
                                          (SQLPOINTER)ba.constData(),
                                          ba.size(),
                                          ind);
                    break;
                }
                else
                {
                    QByteArray &str = tmpStorage[i];
                    str = val.toString().toUtf8();
                    if (*ind != SQL_NULL_DATA)
                        *ind = str.length();
                    int strSize = str.length();

                    r = SQLBindParameter(d->hStmt,
                                          i + 1,
                                          qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                          SQL_C_CHAR,
                                          strSize > 254 ? SQL_LONGVARCHAR : SQL_VARCHAR,
                                          strSize,
                                          0,
                                          (void *)str.constData(),
                                          strSize,
                                          ind);
                    break;
                }
            // fall through
            default: {
                QByteArray &ba = tmpStorage[i];
                if (*ind != SQL_NULL_DATA)
                    *ind = ba.size();
                r = SQLBindParameter(d->hStmt,
                                      i + 1,
                                      qParamType[(QFlag)(bindValueType(i)) & QSql::InOut],
                                      SQL_C_BINARY,
                                      SQL_VARBINARY,
                                      ba.length() + 1,
                                      0,
                                      (void *) ba.constData(),
                                      ba.length() + 1,
                                      ind);
                break; }
        }
        if (r != SQL_SUCCESS) {
            qWarning() << "QODBCResult::exec: unable to bind variable:" << qODBCWarn(d);
            setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                         "Unable to bind variable"), QSqlError::StatementError, d));
            return false;
        }
    }
    r = SQLExecute(d->hStmt);
    if (r != SQL_SUCCESS && r != SQL_SUCCESS_WITH_INFO && r != SQL_NO_DATA) {
        qWarning() << "QODBCResult::exec: Unable to execute statement:" << qODBCWarn(d);
        setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                     "Unable to execute statement"), QSqlError::StatementError, d));
        return false;
    }

    SQLULEN isScrollable = 0;
    r = SQLGetStmtAttr(d->hStmt, SQL_ATTR_CURSOR_SCROLLABLE, &isScrollable, SQL_IS_INTEGER, 0);
    if(r == SQL_SUCCESS || r == SQL_SUCCESS_WITH_INFO)
        QSqlResult::setForwardOnly(isScrollable==SQL_NONSCROLLABLE);

    SQLSMALLINT count;
    SQLNumResultCols(d->hStmt, &count);
    if (count) {
        setSelect(true);
        for (int i = 0; i < count; ++i) {
            d->rInf.append(qMakeFieldInfo(d, i));
        }
        d->fieldCache.resize(count);
    } else {
        setSelect(false);
    }
    setActive(true);


    //get out parameters
    if (!hasOutValues())
        return true;

    for (i = 0; i < values.count(); ++i) {
        switch (values.at(i).type()) {
            case QVariant::Date: {
                DATE_STRUCT ds = *((DATE_STRUCT *)tmpStorage.at(i).constData());
                values[i] = QVariant(QDate(ds.year, ds.month, ds.day));
                break; }
            case QVariant::Time: {
                TIME_STRUCT dt = *((TIME_STRUCT *)tmpStorage.at(i).constData());
                values[i] = QVariant(QTime(dt.hour, dt.minute, dt.second));
                break; }
            case QVariant::DateTime: {
                TIMESTAMP_STRUCT dt = *((TIMESTAMP_STRUCT*)
                                        tmpStorage.at(i).constData());
                values[i] = QVariant(QDateTime(QDate(dt.year, dt.month, dt.day),
                               QTime(dt.hour, dt.minute, dt.second, dt.fraction / 1000000)));
                break; }
            case QVariant::Bool:
            case QVariant::Int:
            case QVariant::UInt:
            case QVariant::Double:
            case QVariant::ByteArray:
            case QVariant::LongLong:
            case QVariant::ULongLong:
                //nothing to do
                break;
            case QVariant::String:
                if (d->unicode) {
                    if (bindValueType(i) & QSql::Out) {
                        const QByteArray &first = tmpStorage.at(i);
                        QVarLengthArray<SQLTCHAR> array;
                        array.append((SQLTCHAR *)first.constData(), first.size());
                        values[i] = fromSQLTCHAR(array, first.size()/sizeof(SQLTCHAR*));
                    }
                    break;
                }
                // fall through
            default: {
                if (bindValueType(i) & QSql::Out)
                    values[i] = tmpStorage.at(i);
                break; }
        }
        if (indicators[i] == SQL_NULL_DATA)
            values[i] = QVariant(values[i].type());
    }
    return true;
}

fetch()

bool QODBCResult::fetch ( int  index )

protectedvirtual

Positions the result to an arbitrary (zero-based) row index.

This function is only called if the result is in an active state. Derived classes must reimplement this function and position the result to the row index, and call setAt() with an appropriate value. Return true to indicate success, or false to signify failure.

See also

isActive(), fetchFirst(), fetchLast(), fetchNext(), fetchPrevious()

Implements QSqlResult.

Definition at line 990 of file qsql_odbc.cpp.

{
    if (!driver()->isOpen())
        return false;

    if (isForwardOnly() && i < at())
        return false;
    if (i == at())
        return true;
    d->clearValues();
    int actualIdx = i + 1;
    if (actualIdx <= 0) {
        setAt(QSql::BeforeFirstRow);
        return false;
    }
    SQLRETURN r;
    if (isForwardOnly()) {
        bool ok = true;
        while (ok && i > at())
            ok = fetchNext();
        return ok;
    } else {
        r = SQLFetchScroll(d->hStmt,
                            SQL_FETCH_ABSOLUTE,
                            actualIdx);
    }
    if (r != SQL_SUCCESS) {
        if (r != SQL_NO_DATA)
            setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                "Unable to fetch"), QSqlError::ConnectionError, d));
        return false;
    }
    setAt(i);
    return true;
}

fetchFirst()

bool QODBCResult::fetchFirst ( )

protectedvirtual

Positions the result to the first record (row 0) in the result.

This function is only called if the result is in an active state. Derived classes must reimplement this function and position the result to the first record, and call setAt() with an appropriate value. Return true to indicate success, or false to signify failure.

See also

fetch(), fetchLast()

Implements QSqlResult.

Definition at line 1048 of file qsql_odbc.cpp.

{
    if (isForwardOnly() && at() != QSql::BeforeFirstRow)
        return false;
    SQLRETURN r;
    d->clearValues();
    if (isForwardOnly()) {
        return fetchNext();
    }
    r = SQLFetchScroll(d->hStmt,
                       SQL_FETCH_FIRST,
                       0);
    if (r != SQL_SUCCESS) {
        if (r != SQL_NO_DATA)
            setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                "Unable to fetch first"), QSqlError::ConnectionError, d));
        return false;
    }
    setAt(0);
    return true;
}

fetchLast()

bool QODBCResult::fetchLast ( )

protectedvirtual

Positions the result to the last record (last row) in the result.

This function is only called if the result is in an active state. Derived classes must reimplement this function and position the result to the last record, and call setAt() with an appropriate value. Return true to indicate success, or false to signify failure.

See also

fetch(), fetchFirst()

Implements QSqlResult.

Definition at line 1089 of file qsql_odbc.cpp.

{
    SQLRETURN r;
    d->clearValues();

    if (isForwardOnly()) {
        // cannot seek to last row in forwardOnly mode, so we have to use brute force
        int i = at();
        if (i == QSql::AfterLastRow)
            return false;
        if (i == QSql::BeforeFirstRow)
            i = 0;
        while (fetchNext())
            ++i;
        setAt(i);
        return true;
    }

    r = SQLFetchScroll(d->hStmt,
                       SQL_FETCH_LAST,
                       0);
    if (r != SQL_SUCCESS) {
        if (r != SQL_NO_DATA)
            setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                "Unable to fetch last"), QSqlError::ConnectionError, d));
        return false;
    }
    SQLULEN currRow = 0;
    r = SQLGetStmtAttr(d->hStmt,
                        SQL_ROW_NUMBER,
                        &currRow,
                        SQL_IS_INTEGER,
                        0);
    if (r != SQL_SUCCESS)
        return false;
    setAt(currRow-1);
    return true;
}

fetchNext()

bool QODBCResult::fetchNext ( )

protectedvirtual

Positions the result to the next available record (row) in the result.

This function is only called if the result is in an active state. The default implementation calls fetch() with the next index. Derived classes can reimplement this function and position the result to the next record in some other way, and call setAt() with an appropriate value. Return true to indicate success, or false to signify failure.

See also

fetch(), fetchPrevious()

Reimplemented from QSqlResult.

Definition at line 1026 of file qsql_odbc.cpp.

Referenced by fetch(), fetchFirst(), and fetchLast().

{
    SQLRETURN r;
    d->clearValues();

    if (d->hasSQLFetchScroll)
        r = SQLFetchScroll(d->hStmt,
                           SQL_FETCH_NEXT,
                           0);
    else
        r = SQLFetch(d->hStmt);

    if (r != SQL_SUCCESS && r != SQL_SUCCESS_WITH_INFO) {
        if (r != SQL_NO_DATA)
            setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                "Unable to fetch next"), QSqlError::ConnectionError, d));
        return false;
    }
    setAt(at() + 1);
    return true;
}

fetchPrevious()

bool QODBCResult::fetchPrevious ( )

protectedvirtual

Positions the result to the previous record (row) in the result.

This function is only called if the result is in an active state. The default implementation calls fetch() with the previous index. Derived classes can reimplement this function and position the result to the next record in some other way, and call setAt() with an appropriate value. Return true to indicate success, or false to signify failure.

Reimplemented from QSqlResult.

Definition at line 1070 of file qsql_odbc.cpp.

{
    if (isForwardOnly())
        return false;
    SQLRETURN r;
    d->clearValues();
    r = SQLFetchScroll(d->hStmt,
                       SQL_FETCH_PRIOR,
                       0);
    if (r != SQL_SUCCESS) {
        if (r != SQL_NO_DATA)
            setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                "Unable to fetch previous"), QSqlError::ConnectionError, d));
        return false;
    }
    setAt(at() - 1);
    return true;
}

handle()

QVariant QODBCResult::handle ( ) const

virtual

Returns the low-level database handle for this result set wrapped in a QVariant or an invalid QVariant if there is no handle.

Warning

Use this with uttermost care and only if you know what you're doing.

The handle returned here can become a stale pointer if the result is modified (for example, if you clear it).

The handle can be NULL if the result was not executed yet.

The handle returned here is database-dependent, you should query the type name of the variant before accessing it.

This example retrieves the handle for a sqlite result:

QSqlQuery query = ...
QVariant v = query.result()->handle();
if (v.isValid() && qstrcmp(v.typeName(), "sqlite3_stmt*")) {
    // v.data() returns a pointer to the handle
    sqlite3_stmt *handle = *static_cast<sqlite3_stmt **>(v.data());
    if (handle != 0) { // check that it is not NULL
        ...
    }
}

This snippet returns the handle for PostgreSQL or MySQL:

if (v.typeName() == "PGresult*") {
    PGresult *handle = *static_cast<PGresult **>(v.data());
    if (handle != 0) ...
}

if (v.typeName() == "MYSQL_STMT*") {
    MYSQL_STMT *handle = *static_cast<MYSQL_STMT **>(v.data());
    if (handle != 0) ...
}

See also

QSqlDriver::handle()

Reimplemented from QSqlResult.

Definition at line 1674 of file qsql_odbc.cpp.

{
    return QVariant(qRegisterMetaType<SQLHANDLE>("SQLHANDLE"), &d->hStmt);
}

isNull()

bool QODBCResult::isNull ( int  i )

protectedvirtual

Returns true if the field at position index in the current row is null; otherwise returns false.

Implements QSqlResult.

Definition at line 1228 of file qsql_odbc.cpp.

{
    if (field < 0 || field > d->fieldCache.size())
        return true;
    if (field <= d->fieldCacheIdx) {
        // since there is no good way to find out whether the value is NULL
        // without fetching the field we'll fetch it here.
        // (data() also sets the NULL flag)
        data(field);
    }
    return d->fieldCache.at(field).isNull();
}

nextResult()

bool QODBCResult::nextResult ( )

protected

Definition at line 1679 of file qsql_odbc.cpp.

Referenced by virtual_hook().

{
    setActive(false);
    setAt(QSql::BeforeFirstRow);
    d->rInf.clear();
    d->fieldCache.clear();
    d->fieldCacheIdx = 0;
    setSelect(false);

    SQLRETURN r = SQLMoreResults(d->hStmt);
    if (r != SQL_SUCCESS) {
        if (r == SQL_SUCCESS_WITH_INFO) {
            int nativeCode = -1;
            QString message = qODBCWarn(d, &nativeCode);
            qWarning() << "QODBCResult::nextResult():" << message;
        } else {
            if (r != SQL_NO_DATA)
                setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                    "Unable to fetch last"), QSqlError::ConnectionError, d));
            return false;
        }
    }

    SQLSMALLINT count;
    SQLNumResultCols(d->hStmt, &count);
    if (count) {
        setSelect(true);
        for (int i = 0; i < count; ++i) {
            d->rInf.append(qMakeFieldInfo(d, i));
        }
        d->fieldCache.resize(count);
    } else {
        setSelect(false);
    }
    setActive(true);

    return true;
}

numRowsAffected()

int QODBCResult::numRowsAffected ( )

protectedvirtual

Returns the number of rows affected by the last query executed, or -1 if it cannot be determined or if the query is a SELECT statement.

See also

size()

Implements QSqlResult.

Definition at line 1246 of file qsql_odbc.cpp.

{
    SQLLEN affectedRowCount = 0;
    SQLRETURN r = SQLRowCount(d->hStmt, &affectedRowCount);
    if (r == SQL_SUCCESS)
        return affectedRowCount;
    else
        qSqlWarning(QLatin1String("QODBCResult::numRowsAffected: Unable to count affected rows"), d);
    return -1;
}

prepare()

bool QODBCResult::prepare ( const QString &  query )

virtual

Prepares the given query for execution; the query will normally use placeholders so that it can be executed repeatedly.

Returns true if the query is prepared successfully; otherwise returns false.

See also

exec()

Reimplemented from QSqlResult.

Definition at line 1257 of file qsql_odbc.cpp.

{
    setActive(false);
    setAt(QSql::BeforeFirstRow);
    SQLRETURN r;

    d->rInf.clear();
    if (d->hStmt && d->isStmtHandleValid(driver())) {
        r = SQLFreeHandle(SQL_HANDLE_STMT, d->hStmt);
        if (r != SQL_SUCCESS) {
            qSqlWarning(QLatin1String("QODBCResult::prepare: Unable to close statement"), d);
            return false;
        }
    }
    r  = SQLAllocHandle(SQL_HANDLE_STMT,
                         d->dpDbc(),
                         &d->hStmt);
    if (r != SQL_SUCCESS) {
        qSqlWarning(QLatin1String("QODBCResult::prepare: Unable to allocate statement handle"), d);
        return false;
    }

    d->updateStmtHandleState(driver());

    if (d->userForwardOnly) {
        r = SQLSetStmtAttr(d->hStmt,
                            SQL_ATTR_CURSOR_TYPE,
                            (SQLPOINTER)SQL_CURSOR_FORWARD_ONLY,
                            SQL_IS_UINTEGER);
    } else {
        r = SQLSetStmtAttr(d->hStmt,
                            SQL_ATTR_CURSOR_TYPE,
                            (SQLPOINTER)SQL_CURSOR_STATIC,
                            SQL_IS_UINTEGER);
    }
    if (r != SQL_SUCCESS && r != SQL_SUCCESS_WITH_INFO) {
        setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
            "QODBCResult::reset: Unable to set 'SQL_CURSOR_STATIC' as statement attribute. "
            "Please check your ODBC driver configuration"), QSqlError::StatementError, d));
        return false;
    }

#ifdef UNICODE
    r = SQLPrepare(d->hStmt,
                    toSQLTCHAR(query).data(),
                    (SQLINTEGER) query.length());
#else
    QByteArray query8 = query.toUtf8();
    r = SQLPrepare(d->hStmt,
                    (SQLCHAR*) query8.data(),
                    (SQLINTEGER) query8.length());
#endif

    if (r != SQL_SUCCESS) {
        setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                     "Unable to prepare statement"), QSqlError::StatementError, d));
        return false;
    }
    return true;
}

record()

QSqlRecord QODBCResult::record ( ) const

protectedvirtual

Returns the current record if the query is active; otherwise returns an empty QSqlRecord.

The default implementation always returns an empty QSqlRecord.

See also

isActive()

Reimplemented from QSqlResult.

Definition at line 1667 of file qsql_odbc.cpp.

{
    if (!isActive() || !isSelect())
        return QSqlRecord();
    return d->rInf;
}

reset()

bool QODBCResult::reset ( const QString &  query )

protectedvirtual

Sets the result to use the SQL statement query for subsequent data retrieval.

Derived classes must reimplement this function and apply the query to the database. This function is only called after the result is set to an inactive state and is positioned before the first record of the new result. Derived classes should return true if the query was successful and ready to be used, or false otherwise.

See also

setQuery()

Implements QSqlResult.

Definition at line 907 of file qsql_odbc.cpp.

{
    setActive(false);
    setAt(QSql::BeforeFirstRow);
    d->rInf.clear();
    d->fieldCache.clear();
    d->fieldCacheIdx = 0;

    // Always reallocate the statement handle - the statement attributes
    // are not reset if SQLFreeStmt() is called which causes some problems.
    SQLRETURN r;
    if (d->hStmt && d->isStmtHandleValid(driver())) {
        r = SQLFreeHandle(SQL_HANDLE_STMT, d->hStmt);
        if (r != SQL_SUCCESS) {
            qSqlWarning(QLatin1String("QODBCResult::reset: Unable to free statement handle"), d);
            return false;
        }
    }
    r  = SQLAllocHandle(SQL_HANDLE_STMT,
                         d->dpDbc(),
                         &d->hStmt);
    if (r != SQL_SUCCESS) {
        qSqlWarning(QLatin1String("QODBCResult::reset: Unable to allocate statement handle"), d);
        return false;
    }

    d->updateStmtHandleState(driver());

    if (d->userForwardOnly) {
        r = SQLSetStmtAttr(d->hStmt,
                            SQL_ATTR_CURSOR_TYPE,
                            (SQLPOINTER)SQL_CURSOR_FORWARD_ONLY,
                            SQL_IS_UINTEGER);
    } else {
        r = SQLSetStmtAttr(d->hStmt,
                            SQL_ATTR_CURSOR_TYPE,
                            (SQLPOINTER)SQL_CURSOR_STATIC,
                            SQL_IS_UINTEGER);
    }
    if (r != SQL_SUCCESS && r != SQL_SUCCESS_WITH_INFO) {
        setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
            "QODBCResult::reset: Unable to set 'SQL_CURSOR_STATIC' as statement attribute. "
            "Please check your ODBC driver configuration"), QSqlError::StatementError, d));
        return false;
    }

#ifdef UNICODE
    r = SQLExecDirect(d->hStmt,
                       toSQLTCHAR(query).data(),
                       (SQLINTEGER) query.length());
#else
    QByteArray query8 = query.toUtf8();
    r = SQLExecDirect(d->hStmt,
                       (SQLCHAR*) query8.data(),
                       (SQLINTEGER) query8.length());
#endif
    if (r != SQL_SUCCESS && r != SQL_SUCCESS_WITH_INFO && r!= SQL_NO_DATA) {
        setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                     "Unable to execute statement"), QSqlError::StatementError, d));
        return false;
    }

    SQLULEN isScrollable = 0;
    r = SQLGetStmtAttr(d->hStmt, SQL_ATTR_CURSOR_SCROLLABLE, &isScrollable, SQL_IS_INTEGER, 0);
    if(r == SQL_SUCCESS || r == SQL_SUCCESS_WITH_INFO)
        QSqlResult::setForwardOnly(isScrollable==SQL_NONSCROLLABLE);

    SQLSMALLINT count;
    SQLNumResultCols(d->hStmt, &count);
    if (count) {
        setSelect(true);
        for (int i = 0; i < count; ++i) {
            d->rInf.append(qMakeFieldInfo(d, i));
        }
        d->fieldCache.resize(count);
    } else {
        setSelect(false);
    }
    setActive(true);

    return true;
}

setForwardOnly()

void QODBCResult::setForwardOnly ( bool  forward )

virtual

Sets forward only mode to forward.

If forward is true, only fetchNext() is allowed for navigating the results. Forward only mode needs much less memory since results do not have to be cached. By default, this feature is disabled.

Setting forward only to false is a suggestion to the database engine, which has the final say on whether a result set is forward only or scrollable. isForwardOnly() will always return the correct status of the result set.

Note

Calling setForwardOnly after execution of the query will result in unexpected results at best, and crashes at worst.

See also

isForwardOnly(), fetchNext(), QSqlQuery::setForwardOnly()

Reimplemented from QSqlResult.

Definition at line 1734 of file qsql_odbc.cpp.

{
    d->userForwardOnly = forward;
    QSqlResult::setForwardOnly(forward);
}

size()

int QODBCResult::size ( )

protectedvirtual

Returns the size of the SELECT result, or -1 if it cannot be determined or if the query is not a SELECT statement.

See also

numRowsAffected()

Implements QSqlResult.

Definition at line 1241 of file qsql_odbc.cpp.

{
    return -1;
}

virtual_hook()

void QODBCResult::virtual_hook ( int  id, void *  data  )

protectedvirtual

Warning

This function is not part of the public interface.

Reimplemented from QSqlResult.

Definition at line 1718 of file qsql_odbc.cpp.

{
    switch (id) {
    case QSqlResult::DetachFromResultSet:
        if (d->hStmt)
            SQLCloseCursor(d->hStmt);
        break;
    case QSqlResult::NextResult:
        Q_ASSERT(data);
        *static_cast<bool*>(data) = nextResult();
        break;
    default:
        QSqlResult::virtual_hook(id, data);
    }
}

Properties

d

QODBCPrivate* QODBCResult::d

private

Definition at line 110 of file qsql_odbc.h.

Referenced by data(), exec(), fetch(), fetchFirst(), fetchLast(), fetchNext(), fetchPrevious(), handle(), isNull(), nextResult(), numRowsAffected(), prepare(), QODBCResult(), record(), reset(), setForwardOnly(), virtual_hook(), and ~QODBCResult().

---

The documentation for this class was generated from the following files:

• /src/sql/drivers/odbc/qsql_odbc.h
• /src/sql/drivers/odbc/qsql_odbc.cpp