- Qt 6.6
- Qt SQL
- C++ Classes
- QSqlError
- Qt 6.6.1 Reference Documentation

# 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

- List of all members, including inherited members
- QSqlError is part of Database Classes.

## 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.

Constant | Value | Description
--- | --- | ---
`QSqlError::NoError` | `0` | No error occurred.
`QSqlError::ConnectionError` | `1` | Connection error.
`QSqlError::StatementError` | `2` | SQL statement syntax error.
`QSqlError::TransactionError` | `3` | Transaction failed error.
`QSqlError::UnknownError` | `4` | Unknown 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.