QSqlError Class

The QSqlError class provides SQL database error information. More...

Header: #include <QSqlError>
CMake: find_package(Qt6 REQUIRED COMPONENTS Sql)
target_link_libraries(mytarget PRIVATE Qt6::Sql)
qmake: QT += sql

Public Types

enum ErrorType { NoError, ConnectionError, StatementError, TransactionError, UnknownError }

Public Functions

QSqlError(const QString &driverText = QString(), const QString &databaseText = QString(), QSqlError::ErrorType type = NoError, const QString &code = QString())
QSqlError(const QSqlError &other)
QSqlError(QSqlError &&other)
~QSqlError()
QString databaseText() const
QString driverText() const
bool isValid() const
QString nativeErrorCode() const
void swap(QSqlError &other)
QString text() const
QSqlError::ErrorType type() const
bool operator!=(const QSqlError &other) const
QSqlError &operator=(const QSqlError &other)
QSqlError &operator=(QSqlError &&other)
bool operator==(const QSqlError &other) const

Detailed Description

A QSqlError object can provide database-specific error data, including the driverText() and databaseText() messages (or both concatenated together as text()), and the nativeErrorCode() and type().

See also QSqlDatabase::lastError() and QSqlQuery::lastError().

Member Type Documentation

enum QSqlError::ErrorType

This enum type describes the context in which the error occurred, e.g., a connection error, a statement error, etc.

ConstantValueDescription
QSqlError::NoError0No error occurred.
QSqlError::ConnectionError1Connection error.
QSqlError::StatementError2SQL statement syntax error.
QSqlError::TransactionError3Transaction failed error.
QSqlError::UnknownError4Unknown error.

Member Function Documentation

QSqlError::QSqlError(const QString &driverText = QString(), const QString &databaseText = QString(), QSqlError::ErrorType type = NoError, const QString &code = QString())

Constructs an error containing the driver error text driverText, the database-specific error text databaseText, the type type and the error code code.

QSqlError::QSqlError(const QSqlError &other)

Creates a copy of other.

[noexcept] QSqlError::QSqlError(QSqlError &&other)

Move-constructs a QSqlError instance, making it point at the same object that other was pointing to.

Note: The moved-from object other is placed in a partially-formed state, in which the only valid operations are destruction and assignment of a new value.

[noexcept] QSqlError::~QSqlError()

Destroys the object and frees any allocated resources.

QString QSqlError::databaseText() const

Returns the text of the error as reported by the database. This may contain database-specific descriptions; it may be empty.

See also driverText() and text().

QString QSqlError::driverText() const

Returns the text of the error as reported by the driver. This may contain database-specific descriptions. It may also be empty.

See also databaseText() and text().

bool QSqlError::isValid() const

Returns true if an error is set, otherwise false.

Example:

 QSqlQueryModel model;
 model.setQuery("select * from myTable");
 if (model.lastError().isValid())
     qDebug() << model.lastError();

See also type().

QString QSqlError::nativeErrorCode() const

Returns the database-specific error code, or an empty string if it cannot be determined.

Note: Some drivers (like DB2 or ODBC) may return more than one error code. When this happens, ; is used as separator between the error codes.

[noexcept] void QSqlError::swap(QSqlError &other)

Swaps error other with this error. This operation is very fast and never fails.

QString QSqlError::text() const

This is a convenience function that returns databaseText() and driverText() concatenated into a single string.

See also driverText() and databaseText().

QSqlError::ErrorType QSqlError::type() const

Returns the error type, or -1 if the type cannot be determined.

bool QSqlError::operator!=(const QSqlError &other) const

Compare the other error's type() and nativeErrorCode() to this error and returns true if it is not equal.

QSqlError &QSqlError::operator=(const QSqlError &other)

Assigns the other error's values to this error.

[noexcept] QSqlError &QSqlError::operator=(QSqlError &&other)

Move-assigns other to this QSqlError instance.

Note: The moved-from object other is placed in a partially-formed state, in which the only valid operations are destruction and assignment of a new value.

bool QSqlError::operator==(const QSqlError &other) const

Compare the other error's type() and nativeErrorCode() to this error and returns true, if it equal.