/**************************************************************************** ** ** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/ ** ** This file is part of the QtSql module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** GNU Lesser General Public License Usage ** This file may be used under the terms of the GNU Lesser General Public ** License version 2.1 as published by the Free Software Foundation and ** appearing in the file LICENSE.LGPL included in the packaging of this ** file. Please review the following information to ensure the GNU Lesser ** General Public License version 2.1 requirements will be met: ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** In addition, as a special exception, Nokia gives you certain additional ** rights. These rights are described in the Nokia Qt LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU General ** Public License version 3.0 as published by the Free Software Foundation ** and appearing in the file LICENSE.GPL included in the packaging of this ** file. Please review the following information to ensure the GNU General ** Public License version 3.0 requirements will be met: ** http://www.gnu.org/copyleft/gpl.html. ** ** Other Usage ** Alternatively, this file may be used in accordance with the terms and ** conditions contained in a signed written agreement between you and Nokia. ** ** ** ** ** ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qsqldatabase.h" #include "qsqlquery.h" #ifdef Q_OS_WIN32 // Conflicting declarations of LPCBYTE in sqlfront.h and winscard.h #define _WINSCARD_H_ #endif #ifdef QT_SQL_PSQL #include "../drivers/psql/qsql_psql.h" #endif #ifdef QT_SQL_MYSQL #include "../drivers/mysql/qsql_mysql.h" #endif #ifdef QT_SQL_ODBC #include "../drivers/odbc/qsql_odbc.h" #endif #ifdef QT_SQL_OCI #include "../drivers/oci/qsql_oci.h" #endif #ifdef QT_SQL_TDS // conflicting RETCODE typedef between odbc and freetds #define RETCODE DBRETCODE #include "../drivers/tds/qsql_tds.h" #undef RETCODE #endif #ifdef QT_SQL_DB2 #include "../drivers/db2/qsql_db2.h" #endif #ifdef QT_SQL_SQLITE #include "../drivers/sqlite/qsql_sqlite.h" #endif #ifdef QT_SQL_SQLITE2 #include "../drivers/sqlite2/qsql_sqlite2.h" #endif #ifdef QT_SQL_IBASE #undef SQL_FLOAT // avoid clash with ODBC #undef SQL_DOUBLE #undef SQL_TIMESTAMP #undef SQL_TYPE_TIME #undef SQL_TYPE_DATE #undef SQL_DATE #define SCHAR IBASE_SCHAR // avoid clash with ODBC (older versions of ibase.h with Firebird) #include "../drivers/ibase/qsql_ibase.h" #undef SCHAR #endif #include "qdebug.h" #include "qcoreapplication.h" #include "qreadwritelock.h" #include "qsqlresult.h" #include "qsqldriver.h" #include "qsqldriverplugin.h" #include "qsqlindex.h" #include "private/qfactoryloader_p.h" #include "private/qsqlnulldriver_p.h" #include "qmutex.h" #include "qhash.h" #include QT_BEGIN_NAMESPACE #ifndef QT_NO_LIBRARY Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader, (QSqlDriverFactoryInterface_iid, QLatin1String("/sqldrivers"))) #endif QT_STATIC_CONST_IMPL char *QSqlDatabase::defaultConnection = "qt_sql_default_connection"; typedef QHash DriverDict; class QConnectionDict: public QHash { public: inline bool contains_ts(const QString &key) { QReadLocker locker(&lock); return contains(key); } inline QStringList keys_ts() const { QReadLocker locker(&lock); return keys(); } mutable QReadWriteLock lock; }; Q_GLOBAL_STATIC(QConnectionDict, dbDict) class QSqlDatabasePrivate { public: QSqlDatabasePrivate(QSqlDatabase *d, QSqlDriver *dr = 0): ref(1), q(d), driver(dr), port(-1) { precisionPolicy = QSql::LowPrecisionDouble; } QSqlDatabasePrivate(const QSqlDatabasePrivate &other); ~QSqlDatabasePrivate(); void init(const QString& type); void copy(const QSqlDatabasePrivate *other); void disable(); QAtomicInt ref; QSqlDatabase *q; QSqlDriver* driver; QString dbname; QString uname; QString pword; QString hname; QString drvName; int port; QString connOptions; QString connName; QSql::NumericalPrecisionPolicy precisionPolicy; static QSqlDatabasePrivate *shared_null(); static QSqlDatabase database(const QString& name, bool open); static void addDatabase(const QSqlDatabase &db, const QString & name); static void removeDatabase(const QString& name); static void invalidateDb(const QSqlDatabase &db, const QString &name, bool doWarn = true); static DriverDict &driverDict(); static void cleanConnections(); }; QSqlDatabasePrivate::QSqlDatabasePrivate(const QSqlDatabasePrivate &other) : ref(1) { q = other.q; dbname = other.dbname; uname = other.uname; pword = other.pword; hname = other.hname; drvName = other.drvName; port = other.port; connOptions = other.connOptions; driver = other.driver; precisionPolicy = other.precisionPolicy; } QSqlDatabasePrivate::~QSqlDatabasePrivate() { if (driver != shared_null()->driver) delete driver; } void QSqlDatabasePrivate::cleanConnections() { QConnectionDict *dict = dbDict(); Q_ASSERT(dict); QWriteLocker locker(&dict->lock); QConnectionDict::iterator it = dict->begin(); while (it != dict->end()) { invalidateDb(it.value(), it.key(), false); ++it; } dict->clear(); } static bool qDriverDictInit = false; static void cleanDriverDict() { qDeleteAll(QSqlDatabasePrivate::driverDict()); QSqlDatabasePrivate::driverDict().clear(); QSqlDatabasePrivate::cleanConnections(); qDriverDictInit = false; } DriverDict &QSqlDatabasePrivate::driverDict() { static DriverDict dict; if (!qDriverDictInit) { qDriverDictInit = true; qAddPostRoutine(cleanDriverDict); } return dict; } QSqlDatabasePrivate *QSqlDatabasePrivate::shared_null() { static QSqlNullDriver dr; static QSqlDatabasePrivate n(NULL, &dr); return &n; } void QSqlDatabasePrivate::invalidateDb(const QSqlDatabase &db, const QString &name, bool doWarn) { if (db.d->ref.load() != 1 && doWarn) { qWarning("QSqlDatabasePrivate::removeDatabase: connection '%s' is still in use, " "all queries will cease to work.", name.toLocal8Bit().constData()); db.d->disable(); db.d->connName.clear(); } } void QSqlDatabasePrivate::removeDatabase(const QString &name) { QConnectionDict *dict = dbDict(); Q_ASSERT(dict); QWriteLocker locker(&dict->lock); if (!dict->contains(name)) return; invalidateDb(dict->take(name), name); } void QSqlDatabasePrivate::addDatabase(const QSqlDatabase &db, const QString &name) { QConnectionDict *dict = dbDict(); Q_ASSERT(dict); QWriteLocker locker(&dict->lock); if (dict->contains(name)) { invalidateDb(dict->take(name), name); qWarning("QSqlDatabasePrivate::addDatabase: duplicate connection name '%s', old " "connection removed.", name.toLocal8Bit().data()); } dict->insert(name, db); db.d->connName = name; } /*! \internal */ QSqlDatabase QSqlDatabasePrivate::database(const QString& name, bool open) { const QConnectionDict *dict = dbDict(); Q_ASSERT(dict); dict->lock.lockForRead(); QSqlDatabase db = dict->value(name); dict->lock.unlock(); if (db.isValid() && !db.isOpen() && open) { if (!db.open()) qWarning() << "QSqlDatabasePrivate::database: unable to open database:" << db.lastError().text(); } return db; } /*! \internal Copies the connection data from \a other. */ void QSqlDatabasePrivate::copy(const QSqlDatabasePrivate *other) { q = other->q; dbname = other->dbname; uname = other->uname; pword = other->pword; hname = other->hname; drvName = other->drvName; port = other->port; connOptions = other->connOptions; precisionPolicy = other->precisionPolicy; } void QSqlDatabasePrivate::disable() { if (driver != shared_null()->driver) { delete driver; driver = shared_null()->driver; } } /*! \class QSqlDriverCreatorBase \brief The QSqlDriverCreatorBase class is the base class for SQL driver factories. \ingroup database \inmodule QtSql Reimplement createObject() to return an instance of the specific QSqlDriver subclass that you want to provide. See QSqlDatabase::registerSqlDriver() for details. \sa QSqlDriverCreator */ /*! \fn QSqlDriverCreatorBase::~QSqlDriverCreatorBase() Destroys the SQL driver creator object. */ /*! \fn QSqlDriver *QSqlDriverCreatorBase::createObject() const Reimplement this function to returns a new instance of a QSqlDriver subclass. */ /*! \class QSqlDriverCreator \brief The QSqlDriverCreator class is a template class that provides a SQL driver factory for a specific driver type. \ingroup database \inmodule QtSql QSqlDriverCreator instantiates objects of type T, where T is a QSqlDriver subclass. See QSqlDatabase::registerSqlDriver() for details. */ /*! \fn QSqlDriver *QSqlDriverCreator::createObject() const \reimp */ /*! \class QSqlDatabase \brief The QSqlDatabase class represents a connection to a database. \ingroup database \inmodule QtSql The QSqlDatabase class provides an interface for accessing a database through a connection. An instance of QSqlDatabase represents the connection. The connection provides access to the database via one of the \l{SQL Database Drivers#Supported Databases} {supported database drivers}, which are derived from QSqlDriver. Alternatively, you can subclass your own database driver from QSqlDriver. See \l{How to Write Your Own Database Driver} for more information. Create a connection (i.e., an instance of QSqlDatabase) by calling one of the static addDatabase() functions, where you specify \l{SQL Database Drivers#Supported Databases} {the driver or type of driver} to use (i.e., what kind of database will you access?) and a connection name. A connection is known by its own name, \e{not} by the name of the database it connects to. You can have multiple connections to one database. QSqlDatabase also supports the concept of a \e{default} connection, which is the unnamed connection. To create the default connection, don't pass the connection name argument when you call addDatabase(). Subsequently, when you call any static member function that takes the connection name argument, if you don't pass the connection name argument, the default connection is assumed. The following snippet shows how to create and open a default connection to a PostgreSQL database: \snippet doc/src/snippets/sqldatabase/sqldatabase.cpp 0 Once the QSqlDatabase object has been created, set the connection parameters with setDatabaseName(), setUserName(), setPassword(), setHostName(), setPort(), and setConnectOptions(). Then call open() to activate the physical connection to the database. The connection is not usable until you open it. The connection defined above will be the \e{default} connection, because we didn't give a connection name to \l{QSqlDatabase::} {addDatabase()}. Subsequently, you can get the default connection by calling database() without the connection name argument: \snippet doc/src/snippets/sqldatabase/sqldatabase.cpp 1 QSqlDatabase is a value class. Changes made to a database connection via one instance of QSqlDatabase will affect other instances of QSqlDatabase that represent the same connection. Use cloneDatabase() to create an independent database connection based on an existing one. If you create multiple database connections, specify a unique connection name for each one, when you call addDatabase(). Use database() with a connection name to get that connection. Use removeDatabase() with a connection name to remove a connection. QSqlDatabase outputs a warning if you try to remove a connection referenced by other QSqlDatabase objects. Use contains() to see if a given connection name is in the list of connections. Once a connection is established, you can call tables() to get the list of tables in the database, call primaryIndex() to get a table's primary index, and call record() to get meta-information about a table's fields (e.g., field names). \note QSqlDatabase::exec() is deprecated. Use QSqlQuery::exec() instead. If the driver supports transactions, use transaction() to start a transaction, and commit() or rollback() to complete it. Use \l{QSqlDriver::} {hasFeature()} to ask if the driver supports transactions. \note When using transactions, you must start the transaction before you create your query. If an error occurrs, lastError() will return information about it. Get the names of the available SQL drivers with drivers(). Check for the presence of a particular driver with isDriverAvailable(). If you have created your own custom driver, you must register it with registerSqlDriver(). \sa QSqlDriver, QSqlQuery, {QtSql Module}, {Threads and the SQL Module} */ /*! \fn QSqlDatabase QSqlDatabase::addDatabase(const QString &type, const QString &connectionName) \threadsafe Adds a database to the list of database connections using the driver \a type and the connection name \a connectionName. If there already exists a database connection called \a connectionName, that connection is removed. The database connection is referred to by \a connectionName. The newly added database connection is returned. If \a type is not available or could not be loaded, isValid() returns false. If \a connectionName is not specified, the new connection becomes the default connection for the application, and subsequent calls to database() without the connection name argument will return the default connection. If a \a connectionName is provided here, use database(\a connectionName) to retrieve the connection. \warning If you add a connection with the same name as an existing connection, the new connection replaces the old one. If you call this function more than once without specifying \a connectionName, the default connection will be the one replaced. Before using the connection, it must be initialized. e.g., call some or all of setDatabaseName(), setUserName(), setPassword(), setHostName(), setPort(), and setConnectOptions(), and, finally, open(). \sa database() removeDatabase() {Threads and the SQL Module} */ QSqlDatabase QSqlDatabase::addDatabase(const QString &type, const QString &connectionName) { QSqlDatabase db(type); QSqlDatabasePrivate::addDatabase(db, connectionName); return db; } /*! \threadsafe Returns the database connection called \a connectionName. The database connection must have been previously added with addDatabase(). If \a open is true (the default) and the database connection is not already open it is opened now. If no \a connectionName is specified the default connection is used. If \a connectionName does not exist in the list of databases, an invalid connection is returned. \sa isOpen() {Threads and the SQL Module} */ QSqlDatabase QSqlDatabase::database(const QString& connectionName, bool open) { return QSqlDatabasePrivate::database(connectionName, open); } /*! \threadsafe Removes the database connection \a connectionName from the list of database connections. \warning There should be no open queries on the database connection when this function is called, otherwise a resource leak will occur. Example: \snippet doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp 0 The correct way to do it: \snippet doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp 1 To remove the default connection, which may have been created with a call to addDatabase() not specifying a connection name, you can retrieve the default connection name by calling connectionName() on the database returned by database(). Note that if a default database hasn't been created an invalid database will be returned. \sa database() connectionName() {Threads and the SQL Module} */ void QSqlDatabase::removeDatabase(const QString& connectionName) { QSqlDatabasePrivate::removeDatabase(connectionName); } /*! Returns a list of all the available database drivers. \sa registerSqlDriver() */ QStringList QSqlDatabase::drivers() { QStringList list; #ifdef QT_SQL_PSQL list << QLatin1String("QPSQL7"); list << QLatin1String("QPSQL"); #endif #ifdef QT_SQL_MYSQL list << QLatin1String("QMYSQL3"); list << QLatin1String("QMYSQL"); #endif #ifdef QT_SQL_ODBC list << QLatin1String("QODBC3"); list << QLatin1String("QODBC"); #endif #ifdef QT_SQL_OCI list << QLatin1String("QOCI8"); list << QLatin1String("QOCI"); #endif #ifdef QT_SQL_TDS list << QLatin1String("QTDS7"); list << QLatin1String("QTDS"); #endif #ifdef QT_SQL_DB2 list << QLatin1String("QDB2"); #endif #ifdef QT_SQL_SQLITE list << QLatin1String("QSQLITE"); #endif #ifdef QT_SQL_SQLITE2 list << QLatin1String("QSQLITE2"); #endif #ifdef QT_SQL_IBASE list << QLatin1String("QIBASE"); #endif #ifndef QT_NO_LIBRARY if (QFactoryLoader *fl = loader()) { QStringList keys = fl->keys(); for (QStringList::const_iterator i = keys.constBegin(); i != keys.constEnd(); ++i) { if (!list.contains(*i)) list << *i; } } #endif DriverDict dict = QSqlDatabasePrivate::driverDict(); for (DriverDict::const_iterator i = dict.constBegin(); i != dict.constEnd(); ++i) { if (!list.contains(i.key())) list << i.key(); } return list; } /*! This function registers a new SQL driver called \a name, within the SQL framework. This is useful if you have a custom SQL driver and don't want to compile it as a plugin. Example: \snippet doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp 2 QSqlDatabase takes ownership of the \a creator pointer, so you mustn't delete it yourself. \sa drivers() */ void QSqlDatabase::registerSqlDriver(const QString& name, QSqlDriverCreatorBase *creator) { delete QSqlDatabasePrivate::driverDict().take(name); if (creator) QSqlDatabasePrivate::driverDict().insert(name, creator); } /*! \threadsafe Returns true if the list of database connections contains \a connectionName; otherwise returns false. \sa connectionNames(), database(), {Threads and the SQL Module} */ bool QSqlDatabase::contains(const QString& connectionName) { return dbDict()->contains_ts(connectionName); } /*! \threadsafe Returns a list containing the names of all connections. \sa contains(), database(), {Threads and the SQL Module} */ QStringList QSqlDatabase::connectionNames() { return dbDict()->keys_ts(); } /*! \overload Creates a QSqlDatabase connection that uses the driver referred to by \a type. If the \a type is not recognized, the database connection will have no functionality. The currently available driver types are: \table \header \li Driver Type \li Description \row \li QDB2 \li IBM DB2 \row \li QIBASE \li Borland InterBase Driver \row \li QMYSQL \li MySQL Driver \row \li QOCI \li Oracle Call Interface Driver \row \li QODBC \li ODBC Driver (includes Microsoft SQL Server) \row \li QPSQL \li PostgreSQL Driver \row \li QSQLITE \li SQLite version 3 or above \row \li QSQLITE2 \li SQLite version 2 \row \li QTDS \li Sybase Adaptive Server \endtable Additional third party drivers, including your own custom drivers, can be loaded dynamically. \sa {SQL Database Drivers}, registerSqlDriver(), drivers() */ QSqlDatabase::QSqlDatabase(const QString &type) { d = new QSqlDatabasePrivate(this); d->init(type); } /*! \overload Creates a database connection using the given \a driver. */ QSqlDatabase::QSqlDatabase(QSqlDriver *driver) { d = new QSqlDatabasePrivate(this, driver); } /*! Creates an empty, invalid QSqlDatabase object. Use addDatabase(), removeDatabase(), and database() to get valid QSqlDatabase objects. */ QSqlDatabase::QSqlDatabase() { d = QSqlDatabasePrivate::shared_null(); d->ref.ref(); } /*! Creates a copy of \a other. */ QSqlDatabase::QSqlDatabase(const QSqlDatabase &other) { d = other.d; d->ref.ref(); } /*! Assigns \a other to this object. */ QSqlDatabase &QSqlDatabase::operator=(const QSqlDatabase &other) { qAtomicAssign(d, other.d); return *this; } /*! \internal Create the actual driver instance \a type. */ void QSqlDatabasePrivate::init(const QString &type) { drvName = type; if (!driver) { #ifdef QT_SQL_PSQL if (type == QLatin1String("QPSQL") || type == QLatin1String("QPSQL7")) driver = new QPSQLDriver(); #endif #ifdef QT_SQL_MYSQL if (type == QLatin1String("QMYSQL") || type == QLatin1String("QMYSQL3")) driver = new QMYSQLDriver(); #endif #ifdef QT_SQL_ODBC if (type == QLatin1String("QODBC") || type == QLatin1String("QODBC3")) driver = new QODBCDriver(); #endif #ifdef QT_SQL_OCI if (type == QLatin1String("QOCI") || type == QLatin1String("QOCI8")) driver = new QOCIDriver(); #endif #ifdef QT_SQL_TDS if (type == QLatin1String("QTDS") || type == QLatin1String("QTDS7")) driver = new QTDSDriver(); #endif #ifdef QT_SQL_DB2 if (type == QLatin1String("QDB2")) driver = new QDB2Driver(); #endif #ifdef QT_SQL_SQLITE if (type == QLatin1String("QSQLITE")) driver = new QSQLiteDriver(); #endif #ifdef QT_SQL_SQLITE2 if (type == QLatin1String("QSQLITE2")) driver = new QSQLite2Driver(); #endif #ifdef QT_SQL_IBASE if (type == QLatin1String("QIBASE")) driver = new QIBaseDriver(); #endif } if (!driver) { DriverDict dict = QSqlDatabasePrivate::driverDict(); for (DriverDict::const_iterator it = dict.constBegin(); it != dict.constEnd() && !driver; ++it) { if (type == it.key()) { driver = ((QSqlDriverCreatorBase*)(*it))->createObject(); } } } #ifndef QT_NO_LIBRARY if (!driver && loader()) { if (QSqlDriverFactoryInterface *factory = qobject_cast(loader()->instance(type))) driver = factory->create(type); } #endif // QT_NO_LIBRARY if (!driver) { qWarning("QSqlDatabase: %s driver not loaded", type.toLatin1().data()); qWarning("QSqlDatabase: available drivers: %s", QSqlDatabase::drivers().join(QLatin1String(" ")).toLatin1().data()); if (QCoreApplication::instance() == 0) qWarning("QSqlDatabase: an instance of QCoreApplication is required for loading driver plugins"); driver = shared_null()->driver; } } /*! Destroys the object and frees any allocated resources. If this is the last QSqlDatabase object that uses a certain database connection, the database connection is automatically closed. \sa close() */ QSqlDatabase::~QSqlDatabase() { if (!d->ref.deref()) { close(); delete d; } } /*! Executes a SQL statement on the database and returns a QSqlQuery object. Use lastError() to retrieve error information. If \a query is empty, an empty, invalid query is returned and lastError() is not affected. \sa QSqlQuery, lastError() */ QSqlQuery QSqlDatabase::exec(const QString & query) const { QSqlQuery r(d->driver->createResult()); if (!query.isEmpty()) { r.exec(query); d->driver->setLastError(r.lastError()); } return r; } /*! Opens the database connection using the current connection values. Returns true on success; otherwise returns false. Error information can be retrieved using lastError(). \sa lastError() setDatabaseName() setUserName() setPassword() \sa setHostName() setPort() setConnectOptions() */ bool QSqlDatabase::open() { return d->driver->open(d->dbname, d->uname, d->pword, d->hname, d->port, d->connOptions); } /*! \overload Opens the database connection using the given \a user name and \a password. Returns true on success; otherwise returns false. Error information can be retrieved using the lastError() function. This function does not store the password it is given. Instead, the password is passed directly to the driver for opening the connection and it is then discarded. \sa lastError() */ bool QSqlDatabase::open(const QString& user, const QString& password) { setUserName(user); return d->driver->open(d->dbname, user, password, d->hname, d->port, d->connOptions); } /*! Closes the database connection, freeing any resources acquired, and invalidating any existing QSqlQuery objects that are used with the database. This will also affect copies of this QSqlDatabase object. \sa removeDatabase() */ void QSqlDatabase::close() { d->driver->close(); } /*! Returns true if the database connection is currently open; otherwise returns false. */ bool QSqlDatabase::isOpen() const { return d->driver->isOpen(); } /*! Returns true if there was an error opening the database connection; otherwise returns false. Error information can be retrieved using the lastError() function. */ bool QSqlDatabase::isOpenError() const { return d->driver->isOpenError(); } /*! Begins a transaction on the database if the driver supports transactions. Returns \c{true} if the operation succeeded. Otherwise it returns \c{false}. \sa QSqlDriver::hasFeature(), commit(), rollback() */ bool QSqlDatabase::transaction() { if (!d->driver->hasFeature(QSqlDriver::Transactions)) return false; return d->driver->beginTransaction(); } /*! Commits a transaction to the database if the driver supports transactions and a transaction() has been started. Returns \c{true} if the operation succeeded. Otherwise it returns \c{false}. \note For some databases, the commit will fail and return \c{false} if there is an \l{QSqlQuery::isActive()} {active query} using the database for a \c{SELECT}. Make the query \l{QSqlQuery::isActive()} {inactive} before doing the commit. Call lastError() to get information about errors. \sa QSqlQuery::isActive() QSqlDriver::hasFeature() rollback() */ bool QSqlDatabase::commit() { if (!d->driver->hasFeature(QSqlDriver::Transactions)) return false; return d->driver->commitTransaction(); } /*! Rolls back a transaction on the database, if the driver supports transactions and a transaction() has been started. Returns \c{true} if the operation succeeded. Otherwise it returns \c{false}. \note For some databases, the rollback will fail and return \c{false} if there is an \l{QSqlQuery::isActive()} {active query} using the database for a \c{SELECT}. Make the query \l{QSqlQuery::isActive()} {inactive} before doing the rollback. Call lastError() to get information about errors. \sa QSqlQuery::isActive() QSqlDriver::hasFeature() commit() */ bool QSqlDatabase::rollback() { if (!d->driver->hasFeature(QSqlDriver::Transactions)) return false; return d->driver->rollbackTransaction(); } /*! Sets the connection's database name to \a name. To have effect, the database name must be set \e{before} the connection is \l{open()} {opened}. Alternatively, you can close() the connection, set the database name, and call open() again. \note The \e{database name} is not the \e{connection name}. The connection name must be passed to addDatabase() at connection object create time. For the QOCI (Oracle) driver, the database name is the TNS Service Name. For the QODBC driver, the \a name can either be a DSN, a DSN filename (in which case the file must have a \c .dsn extension), or a connection string. For example, Microsoft Access users can use the following connection string to open an \c .mdb file directly, instead of having to create a DSN entry in the ODBC manager: \snippet doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp 3 There is no default value. \sa databaseName() setUserName() setPassword() setHostName() \sa setPort() setConnectOptions() open() */ void QSqlDatabase::setDatabaseName(const QString& name) { if (isValid()) d->dbname = name; } /*! Sets the connection's user name to \a name. To have effect, the user name must be set \e{before} the connection is \l{open()} {opened}. Alternatively, you can close() the connection, set the user name, and call open() again. There is no default value. \sa userName() setDatabaseName() setPassword() setHostName() \sa setPort() setConnectOptions() open() */ void QSqlDatabase::setUserName(const QString& name) { if (isValid()) d->uname = name; } /*! Sets the connection's password to \a password. To have effect, the password must be set \e{before} the connection is \l{open()} {opened}. Alternatively, you can close() the connection, set the password, and call open() again. There is no default value. \warning This function stores the password in plain text within Qt. Use the open() call that takes a password as parameter to avoid this behavior. \sa password() setUserName() setDatabaseName() setHostName() \sa setPort() setConnectOptions() open() */ void QSqlDatabase::setPassword(const QString& password) { if (isValid()) d->pword = password; } /*! Sets the connection's host name to \a host. To have effect, the host name must be set \e{before} the connection is \l{open()} {opened}. Alternatively, you can close() the connection, set the host name, and call open() again. There is no default value. \sa hostName() setUserName() setPassword() setDatabaseName() \sa setPort() setConnectOptions() open() */ void QSqlDatabase::setHostName(const QString& host) { if (isValid()) d->hname = host; } /*! Sets the connection's port number to \a port. To have effect, the port number must be set \e{before} the connection is \l{open()} {opened}. Alternatively, you can close() the connection, set the port number, and call open() again.. There is no default value. \sa port() setUserName() setPassword() setHostName() \sa setDatabaseName() setConnectOptions() open() */ void QSqlDatabase::setPort(int port) { if (isValid()) d->port = port; } /*! Returns the connection's database name, which may be empty. \note The database name is not the connection name. \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 \li ODBC \li MySQL \li PostgreSQL \row \li \list \li SQL_ATTR_ACCESS_MODE \li SQL_ATTR_LOGIN_TIMEOUT \li SQL_ATTR_CONNECTION_TIMEOUT \li SQL_ATTR_CURRENT_CATALOG \li SQL_ATTR_METADATA_ID \li SQL_ATTR_PACKET_SIZE \li SQL_ATTR_TRACEFILE \li SQL_ATTR_TRACE \li SQL_ATTR_CONNECTION_POOLING \li SQL_ATTR_ODBC_VERSION \endlist \li \list \li CLIENT_COMPRESS \li CLIENT_FOUND_ROWS \li CLIENT_IGNORE_SPACE \li CLIENT_SSL \li CLIENT_ODBC \li CLIENT_NO_SCHEMA \li CLIENT_INTERACTIVE \li UNIX_SOCKET \li MYSQL_OPT_RECONNECT \endlist \li \list \li connect_timeout \li options \li tty \li requiressl \li service \endlist \header \li DB2 \li OCI \li TDS \row \li \list \li SQL_ATTR_ACCESS_MODE \li SQL_ATTR_LOGIN_TIMEOUT \endlist \li \list \li OCI_ATTR_PREFETCH_ROWS \li OCI_ATTR_PREFETCH_MEMORY \endlist \li \e none \header \li SQLite \li Interbase \row \li \list \li QSQLITE_BUSY_TIMEOUT \li QSQLITE_OPEN_READONLY \li QSQLITE_ENABLE_SHARED_CACHE \endlist \li \list \li ISC_DPB_LC_CTYPE \li ISC_DPB_SQL_ROLE_NAME \endlist \endtable Examples: \snippet doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp 4 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); } /*! \fn QSqlDatabase QSqlDatabase::addDatabase(QSqlDriver* driver, const QString& connectionName) This overload is useful when you want to create a database connection with a \l{QSqlDriver} {driver} you instantiated yourself. It might be your own database driver, or you might just need to instantiate one of the Qt drivers yourself. If you do this, it is recommended that you include the driver code in your application. For example, you can create a PostgreSQL connection with your own QPSQL driver like this: \snippet doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp 5 \codeline \snippet doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp 6 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. \note 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. Remember that you must link your application against the database client library. Make sure the client library is in your linker's search path, and add lines like these to your \c{.pro} file: \snippet doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp 7 The method described works for all the supplied drivers. The only difference will be in the driver constructor arguments. Here is a table of the drivers included with Qt, their source code files, and their constructor arguments: \table \header \li Driver \li Class name \li Constructor arguments \li File to include \row \li QPSQL \li QPSQLDriver \li PGconn *connection \li \c qsql_psql.cpp \row \li QMYSQL \li QMYSQLDriver \li MYSQL *connection \li \c qsql_mysql.cpp \row \li QOCI \li QOCIDriver \li OCIEnv *environment, OCISvcCtx *serviceContext \li \c qsql_oci.cpp \row \li QODBC \li QODBCDriver \li SQLHANDLE environment, SQLHANDLE connection \li \c qsql_odbc.cpp \row \li QDB2 \li QDB2 \li SQLHANDLE environment, SQLHANDLE connection \li \c qsql_db2.cpp \row \li QTDS \li QTDSDriver \li LOGINREC *loginRecord, DBPROCESS *dbProcess, const QString &hostName \li \c qsql_tds.cpp \row \li QSQLITE \li QSQLiteDriver \li sqlite *connection \li \c qsql_sqlite.cpp \row \li QIBASE \li QIBaseDriver \li isc_db_handle connection \li \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 blocking when several QSqlQuery objects are used simultaneously. \warning Adding a database connection with the same connection name as an existing connection, causes the existing connection to be replaced by the new one. \warning The SQL framework takes ownership of the \a driver. It must not be deleted. To 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: \snippet doc/src/snippets/code/src_sql_kernel_qsqldatabase.cpp 8 */ bool QSqlDatabase::isValid() const { return d->driver && d->driver != d->shared_null()->driver; } /*! 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 The new connection has not been opened. Before using the new connection, you must call open(). */ 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; } /*! \since 4.4 Returns the connection name, which may be empty. \note The connection name is not the \l{databaseName()} {database name}. \sa addDatabase() */ QString QSqlDatabase::connectionName() const { return d->connName; } /*! \since 4.6 Sets the default numerical precision policy used by queries created on this database connection to \a precisionPolicy. Note: Drivers that don't support fetching numerical values with low precision will ignore the precision policy. You can use QSqlDriver::hasFeature() to find out whether a driver supports this feature. Note: Setting the default precision policy to \a precisionPolicy doesn't affect any currently active queries. \sa QSql::NumericalPrecisionPolicy, numericalPrecisionPolicy(), QSqlQuery::setNumericalPrecisionPolicy(), QSqlQuery::numericalPrecisionPolicy() */ void QSqlDatabase::setNumericalPrecisionPolicy(QSql::NumericalPrecisionPolicy precisionPolicy) { if(driver()) driver()->setNumericalPrecisionPolicy(precisionPolicy); d->precisionPolicy = precisionPolicy; } /*! \since 4.6 Returns the current default precision policy for the database connection. \sa QSql::NumericalPrecisionPolicy, setNumericalPrecisionPolicy(), QSqlQuery::numericalPrecisionPolicy(), QSqlQuery::setNumericalPrecisionPolicy() */ QSql::NumericalPrecisionPolicy QSqlDatabase::numericalPrecisionPolicy() const { if(driver()) return driver()->numericalPrecisionPolicy(); else return d->precisionPolicy; } #ifndef QT_NO_DEBUG_STREAM QDebug 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 QT_END_NAMESPACE