The QSqlDriver class is an abstract base class for accessing specific SQL databases. More..

In Qt Designer's signals and slots editing mode, you can connect objects in a form together using Qt's signals and slots mechanism.Both widgets and layouts can be connected via an intuitive connection interface, using the menu of compatible signals and slots provided by Qt Designer.

I'm at a loss for why this issue is coming up. I've got QOBJECT in the header, the slot is included in: private slots: void slotname; Everything is spelled the same, all the other answers I've found either don't apply or I've already checked to see if they were the cause.
Don't do that, since Qt doesn't support multiple derivation from QObject, not even virtual derivation. The second and subsequent QObject bases are ignored by the QObject system. Thus, to the QObject machinery, the Derived class only derives from QObject, and not from Base - thus it doesn't know about baseSignal.

Public Types

enum	DriverFeature { Transactions, QuerySize, BLOB, Unicode, .., MultipleResultSets }
enum	IdentifierType { FieldName, TableName }
enum	StatementType { WhereStatement, SelectStatement, UpdateStatement, InsertStatement, DeleteStatement }

Public Functions

QSqlDriver(QObject * parent = 0)
~QSqlDriver()
virtual bool	beginTransaction()
virtual void	close() = 0
virtual bool	commitTransaction()
virtual QSqlResult *	createResult() const = 0
virtual QString	escapeIdentifier(const QString & identifier, IdentifierType type) const
virtual QString	formatValue(const QSqlField & field, bool trimStrings = false) const
virtual QVariant	handle() const
virtual bool	hasFeature(DriverFeature feature) const = 0
bool	isIdentifierEscaped(const QString & identifier, IdentifierType type) const
virtual bool	isOpen() const
bool	isOpenError() const
QSqlError	lastError() const
QSql::NumericalPrecisionPolicy	numericalPrecisionPolicy() const
virtual bool	open(const QString & db, const QString & user = QString(), const QString & password = QString(), const QString & host = QString(), int port = -1, const QString & options = QString()) = 0
virtual QSqlIndex	primaryIndex(const QString & tableName) const
virtual QSqlRecord	record(const QString & tableName) const
virtual bool	rollbackTransaction()
void	setNumericalPrecisionPolicy(QSql::NumericalPrecisionPolicy precisionPolicy)
virtual QString	sqlStatement(StatementType type, const QString & tableName, const QSqlRecord & rec, bool preparedStatement) const
QString	stripDelimiters(const QString & identifier, IdentifierType type) const
bool	subscribeToNotification(const QString & name)
QStringList	subscribedToNotifications() const
virtual QStringList	tables(QSql::TableType tableType) const
bool	unsubscribeFromNotification(const QString & name)

29 public functions inherited from QObject

Signals

1 signal inherited from QObject

Protected Functions

virtual void	setLastError(const QSqlError & error)
virtual void	setOpen(bool open)
virtual void	setOpenError(bool error)

8 protected functions inherited from QObject

Protected Slots

bool	isIdentifierEscapedImplementation(const QString & identifier, IdentifierType type) const
QString	stripDelimitersImplementation(const QString & identifier, IdentifierType type) const
bool	subscribeToNotificationImplementation(const QString & name)
QStringList	subscribedToNotificationsImplementation() const
bool	unsubscribeFromNotificationImplementation(const QString & name)

Additional Inherited Members

1 property inherited from QObject
1 public slot inherited from QObject
7 static public members inherited from QObject

Detailed Description

The QSqlDriver class is an abstract base class for accessing specific SQL databases.

This class should not be used directly. Use QSqlDatabase instead.

If you want to create your own SQL drivers, you can subclass this class and reimplement its pure virtual functions and those virtual functions that you need. See How to Write Your Own Database Driver for more information.

See also QSqlDatabase and QSqlResult.

Member Type Documentation

enum QSqlDriver::DriverFeature

This enum contains a list of features a driver might support. Use hasFeature() to query whether a feature is supported or not.

Constant	Value	Description
`QSqlDriver::Transactions`	`0`	Whether the driver supports SQL transactions.
`QSqlDriver::QuerySize`	`1`	Whether the database is capable of reporting the size of a query. Note that some databases do not support returning the size (i.e. number of rows returned) of a query, in which case QSqlQuery::size() will return -1.
`QSqlDriver::BLOB`	`2`	Whether the driver supports Binary Large Object fields.
`QSqlDriver::Unicode`	`3`	Whether the driver supports Unicode strings if the database server does.
`QSqlDriver::PreparedQueries`	`4`	Whether the driver supports prepared query execution.
`QSqlDriver::NamedPlaceholders`	`5`	Whether the driver supports the use of named placeholders.
`QSqlDriver::PositionalPlaceholders`	`6`	Whether the driver supports the use of positional placeholders.
`QSqlDriver::LastInsertId`	`7`	Whether the driver supports returning the Id of the last touched row.
`QSqlDriver::BatchOperations`	`8`	Whether the driver supports batched operations, see QSqlQuery::execBatch()
`QSqlDriver::SimpleLocking`	`9`	Whether the driver disallows a write lock on a table while other queries have a read lock on it.
`QSqlDriver::LowPrecisionNumbers`	`10`	Whether the driver allows fetching numerical values with low precision.
`QSqlDriver::EventNotifications`	`11`	Whether the driver supports database event notifications.
`QSqlDriver::FinishQuery`	`12`	Whether the driver can do any low-level resource cleanup when QSqlQuery::finish() is called.
`QSqlDriver::MultipleResultSets`	`13`	Whether the driver can access multiple result sets returned from batched statements or stored procedures.

More information about supported features can be found in the Qt SQL driver documentation.

See also hasFeature().

enum QSqlDriver::IdentifierType

This enum contains a list of SQL identifier types.

Constant	Value

Qt No Such Slot In Derived Class