close() the connection, call this function and open() the    connection again).    There is no default value.    \sa hostName() setUserName() setPassword() setDatabaseName() setPort() setConnectOptions() open()*/void QSqlDatabase::setHostName(const QString& host){    if (isValid())        d->hname = host;}/*!    Sets the connection's port number to \a port. This must be done    before the connection is opened or it has no effect (or you can    close() the connection, call this function and open() the    connection again).    There is no default value.    \sa port() setUserName() setPassword() setHostName()    setDatabaseName() setConnectOptions() open()*/void QSqlDatabase::setPort(int port){    if (isValid())        d->port = port;}/*!    Returns the connection's database name; it may be empty.    \sa setDatabaseName()*/QString QSqlDatabase::databaseName() const{    return d->dbname;}/*!    Returns the connection's user name; it may be empty.    \sa setUserName()*/QString QSqlDatabase::userName() const{    return d->uname;}/*!    Returns the connection's password. If the password was not set    with setPassword(), and if the password was given in the open()    call, or if no password was used, an empty string is returned.*/QString QSqlDatabase::password() const{    return d->pword;}/*!    Returns the connection's host name. It may be empty.    \sa setHostName()*/QString QSqlDatabase::hostName() const{    return d->hname;}/*!    Returns the connection's driver name.    \sa addDatabase(), driver()*/QString QSqlDatabase::driverName() const{    return d->drvName;}/*!    Returns the connection's port number. The value is undefined if    the port number has not been set.    \sa setPort()*/int QSqlDatabase::port() const{    return d->port;}/*!    Returns the database driver used to access the database    connection.    \sa addDatabase() drivers()*/QSqlDriver* QSqlDatabase::driver() const{    return d->driver;}/*!    Returns information about the last error that occurred on the    database.    Failures that occur in conjunction with an individual query are    reported by QSqlQuery::lastError().    \sa QSqlError, QSqlQuery::lastError()*/QSqlError QSqlDatabase::lastError() const{    return d->driver->lastError();}/*!    Returns a list of the database's tables, system tables and views,    as specified by the parameter \a type.    \sa primaryIndex(), record()*/QStringList QSqlDatabase::tables(QSql::TableType type) const{    return d->driver->tables(type);}/*!    Returns the primary index for table \a tablename. If no primary    index exists an empty QSqlIndex is returned.    \sa tables(), record()*/QSqlIndex QSqlDatabase::primaryIndex(const QString& tablename) const{    return d->driver->primaryIndex(tablename);}/*!    Returns a QSqlRecord populated with the names of all the fields in    the table (or view) called \a tablename. The order in which the    fields appear in the record is undefined. If no such table (or    view) exists, an empty record is returned.*/QSqlRecord QSqlDatabase::record(const QString& tablename) const{    return d->driver->record(tablename);}/*!    Sets database-specific \a options. This must be done before the    connection is opened or it has no effect (or you can close() the    connection, call this function and open() the connection again).    The format of the \a options string is a semicolon separated list    of option names or option=value pairs. The options depend on the    database client used:    \table    \header \i ODBC \i MySQL \i PostgreSQL    \row    \i    \list    \i SQL_ATTR_ACCESS_MODE    \i SQL_ATTR_LOGIN_TIMEOUT    \i SQL_ATTR_CONNECTION_TIMEOUT    \i SQL_ATTR_CURRENT_CATALOG    \i SQL_ATTR_METADATA_ID    \i SQL_ATTR_PACKET_SIZE    \i SQL_ATTR_TRACEFILE    \i SQL_ATTR_TRACE    \i SQL_ATTR_CONNECTION_POOLING    \endlist    \i    \list    \i CLIENT_COMPRESS    \i CLIENT_FOUND_ROWS    \i CLIENT_IGNORE_SPACE    \i CLIENT_SSL    \i CLIENT_ODBC    \i CLIENT_NO_SCHEMA    \i CLIENT_INTERACTIVE    \i UNIX_SOCKET    \endlist    \i    \list    \i connect_timeout    \i options    \i tty    \i requiressl    \i service    \endlist    \header \i DB2 \i OCI \i TDS    \row    \i    \list    \i SQL_ATTR_ACCESS_MODE    \i SQL_ATTR_LOGIN_TIMEOUT    \endlist    \i    \list    \i OCI_ATTR_PREFETCH_ROWS    \i OCI_ATTR_PREFETCH_MEMORY    \endlist    \i    \e none    \header \i SQLite    \row    \i    \list    \i QSQLITE_BUSY_TIMEOUT    \endlist    \endtable    Examples:    \code    ...    // MySQL connection    db.setConnectOptions("CLIENT_SSL=1;CLIENT_IGNORE_SPACE=1"); // use an SSL connection to the server    if (!db.open()) {        db.setConnectOptions(); // clears the connect option string        ...    }    ...    // PostgreSQL connection    db.setConnectOptions("requiressl=1"); // enable PostgreSQL SSL connections    if (!db.open()) {        db.setConnectOptions(); // clear options        ...    }    ...    // ODBC connection    db.setConnectOptions("SQL_ATTR_ACCESS_MODE=SQL_MODE_READ_ONLY;SQL_ATTR_TRACE=SQL_OPT_TRACE_ON"); // set ODBC options    if (!db.open()) {        db.setConnectOptions(); // don't try to set this option        ...    }    \endcode    Refer to the client library documentation for more information    about the different options.    \sa connectOptions()*/void QSqlDatabase::setConnectOptions(const QString &options){    if (isValid())        d->connOptions = options;}/*!    Returns the connection options string used for this connection.    The string may be empty.    \sa setConnectOptions() */QString QSqlDatabase::connectOptions() const{    return d->connOptions;}/*!    Returns true if a driver called \a name is available; otherwise    returns false.    \sa drivers()*/bool QSqlDatabase::isDriverAvailable(const QString& name){    return drivers().contains(name);}/*! \overload    This function is useful if you need to set up the database    connection and instantiate the driver yourself. If you do this,    it is recommended that you include the driver code in your own    application. For example, setting up a custom PostgreSQL    connection and instantiating the QPSQL driver can be done like    this:    \code        #include "qtdir/src/sql/drivers/psql/qsql_psql.cpp"    \endcode    (We assume that \c qtdir is the directory where Qt is installed.)    This will pull in the code that is needed to use the PostgreSQL    client library and to instantiate a QPSQLDriver object, assuming    that you have the PostgreSQL headers somewhere in your include    search path.    \code        PGconn *con = PQconnectdb("host=server user=bart password=simpson dbname=springfield");        QPSQLDriver *drv =  new QPSQLDriver(con);        QSqlDatabase db = QSqlDatabase::addDatabase(drv); // becomes the new default connection        QSqlQuery query;        query.exec("SELECT NAME, ID FROM STAFF");        ...    \endcode    The above code sets up a PostgreSQL connection and instantiates a    QPSQLDriver object. Next, addDatabase() is called to add the    connection to the known connections so that it can be used by the    Qt SQL classes. When a driver is instantiated with a connection    handle (or set of handles), Qt assumes that you have already    opened the database connection.    Remember that you must link your application against the database    client library as well. The simplest way to do this is to add    lines like the ones below to your \c .pro file:    \code        unix:LIBS += -lpq        win32:LIBS += libpqdll.lib    \endcode    You will need to have the client library in your linker's search    path.    The method described above will work for all the drivers, the only    difference is the arguments the driver constructors take. Below is    an overview of the drivers and their constructor arguments.    \table    \header \i Driver \i Class name \i Constructor arguments \i File to include    \row    \i QPSQL    \i QPSQLDriver    \i PGconn *connection    \i \c qsql_psql.cpp    \row    \i QMYSQL    \i QMYSQLDriver    \i MYSQL *connection    \i \c qsql_mysql.cpp    \row    \i QOCI    \i QOCIDriver    \i OCIEnv *environment, OCISvcCtx *serviceContext    \i \c qsql_oci.cpp    \row    \i QODBC    \i QODBCDriver    \i SQLHANDLE environment, SQLHANDLE connection    \i \c qsql_odbc.cpp    \row    \i QDB2    \i QDB2    \i SQLHANDLE environment, SQLHANDLE connection    \i \c qsql_db2.cpp    \row    \i QTDS    \i QTDSDriver    \i LOGINREC *loginRecord, DBPROCESS *dbProcess, const QString &hostName    \i \c qsql_tds.cpp    \row    \i QSQLITE    \i QSQLiteDriver    \i sqlite *connection    \i \c qsql_sqlite.cpp    \row    \i QIBASE    \i QIBaseDriver    \i isc_db_handle connection    \i \c qsql_ibase.cpp    \endtable    The host name (or service name) is needed when constructing    the QTDSDriver for creating new connections for internal    queries. This is to prevent the simultaneous usage of several    QSqlQuery/\l{QSqlCursor} objects from blocking each other.    \warning If you add a database with the same name as an    existing database, the new database will replace the old one.    \warning The SQL framework takes ownership of the \a driver pointer,    and it should not be deleted. If you want to    explicitly remove the connection, use removeDatabase().    \sa drivers()*/QSqlDatabase QSqlDatabase::addDatabase(QSqlDriver* driver, const QString& connectionName){    QSqlDatabase db(driver);    QSqlDatabasePrivate::addDatabase(db, connectionName);    return db;}/*!    Returns true if the QSqlDatabase has a valid driver.    Example:    \code        QSqlDatabase db;        qDebug() << db.isValid();    // Returns false        db = QSqlDatabase::database("sales");        qDebug() << db.isValid();    // Returns true if "sales" connection exists        QSqlDatabase::removeDatabase("sales");        qDebug() << db.isValid();    // Returns false    \endcode*/bool QSqlDatabase::isValid() const{    return d->driver && d->driver != d->shared_null()->driver;}#ifdef QT3_SUPPORT/*!    Use query.record() instead.*/QSqlRecord QSqlDatabase::record(const QSqlQuery& query) const{ return query.record(); }/*!    Use query.record() instead.*/QSqlRecord QSqlDatabase::recordInfo(const QSqlQuery& query) const{ return query.record(); }/*!    \fn QSqlRecord QSqlDatabase::recordInfo(const QString& tablename) const    Use record() instead.*/#endif/*!    Clones the database connection \a other and and stores it as \a    connectionName. All the settings from the original database, e.g.    databaseName(), hostName(), etc., are copied across. Does nothing    if \a other is an invalid database. Returns the newly created    database connection.    Note that the connection is not opened, to use it, it is    necessary to call open() first.*/QSqlDatabase QSqlDatabase::cloneDatabase(const QSqlDatabase &other, const QString &connectionName){    if (!other.isValid())        return QSqlDatabase();    QSqlDatabase db(other.driverName());    db.d->copy(other.d);    QSqlDatabasePrivate::addDatabase(db, connectionName);    return db;}#ifndef QT_NO_DEBUG_STREAMQDebug operator<<(QDebug dbg, const QSqlDatabase &d){    if (!d.isValid()) {        dbg.nospace() << "QSqlDatabase(invalid)";        return dbg.space();    }    dbg.nospace() << "QSqlDatabase(driver=\"" << d.driverName() << "\", database=\""                  << d.databaseName() << "\", host=\"" << d.hostName() << "\", port=" << d.port()                  << ", user=\"" << d.userName() << "\", open=" << d.isOpen() << ")";    return dbg.space();}#endif