QGIS/python/core/auto_generated/qgstransaction.sip.in

/************************************************************************
 * This file has been generated automatically from                      *
 *                                                                      *
 * src/core/qgstransaction.h                                            *
 *                                                                      *
 * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
 ************************************************************************/







class QgsTransaction : QObject /Abstract/
{
%Docstring
This class allows including a set of layers in a database-side transaction,
provided the layer data providers support transactions and are compatible
with each other.

Only layers which are not in edit mode can be included in a transaction,
and all layers need to be in read-only mode for a transaction to be committed
or rolled back.

Layers can only be included in one transaction at a time.

When editing layers which are part of a transaction group, all changes are
sent directly to the data provider (bypassing the undo/redo stack), and the
changes can either be committed or rolled back on the database side via the
QgsTransaction.commit and QgsTransaction.rollback methods.

As long as the transaction is active, the state of all layer features reflects
the current state in the transaction.

Edits on features can get rejected if another conflicting transaction is active.
%End

%TypeHeaderCode
#include "qgstransaction.h"
%End
  public:

    static QgsTransaction *create( const QString &connString, const QString &providerKey ) /Factory/;
%Docstring
Create a transaction for the specified connection string ``connString``
and provider with ``providerKey``.
%End

    static QgsTransaction *create( const QSet<QgsVectorLayer *> &layers ) /Factory/;
%Docstring
Create a transaction which includes the ``layers``.
All layers are expected to have the same connection string and data
provider.
%End

    ~QgsTransaction();

    bool addLayer( QgsVectorLayer *layer );
%Docstring
Add the ``layer`` to the transaction. The layer must not be
in edit mode and the connection string must match.
%End

    bool begin( QString &errorMsg /Out/, int statementTimeout = 20 );
%Docstring
Begin transaction
The ``statementTimeout`` (in seconds) specifies how long an sql statement
is allowed to block QGIS before it is aborted.
Statements can block, if multiple transactions are active and a
statement would produce a conflicting state. In these cases, the
statements block until the conflicting transaction is committed or
rolled back.
Some providers might not honour the statement timeout.
%End

    bool commit( QString &errorMsg /Out/ );
%Docstring
Commit transaction.
%End

    bool rollback( QString &errorMsg /Out/ );
%Docstring
Roll back transaction.
%End

    virtual bool executeSql( const QString &sql, QString &error /Out/, bool isDirty = false, const QString &name = QString() ) = 0;
%Docstring
Execute the ``sql`` string.

:param sql: The sql query to execute
:param error: The error message
:param isDirty: Flag to indicate if the underlying data will be modified
:param name: Name of the transaction ( only used if `isDirty` is true)

:return: true if everything is OK, false otherwise
%End

    static bool supportsTransaction( const QgsVectorLayer *layer );
%Docstring
Checks if the provider of a given ``layer`` supports transactions.
%End

    QString createSavepoint( QString &error /Out/ );
%Docstring
creates a save point
returns empty string on error
returns the last created savepoint if it's not dirty

.. versionadded:: 3.0
%End

    QString createSavepoint( const QString &savePointId, QString &error /Out/ );
%Docstring
creates a save point
returns empty string on error

.. versionadded:: 3.0
%End

    bool rollbackToSavepoint( const QString &name, QString &error /Out/ );
%Docstring
rollback to save point, the save point is maintained and is "undertied"

.. versionadded:: 3.0
%End

    void dirtyLastSavePoint();
%Docstring
dirty save point such that next call to createSavepoint will create a new one

.. versionadded:: 3.0
%End

    QList< QString > savePoints() const;
%Docstring
returns savepoints

.. versionadded:: 3.0
%End

    bool lastSavePointIsDirty() const;
%Docstring
returns the last created savepoint

.. versionadded:: 3.0
%End

  signals:

    void afterRollback();
%Docstring
Emitted after a rollback
%End

    void dirtied( const QString &sql, const QString &name );
%Docstring
Emitted if a sql query is executed and the underlying data is modified
%End

  protected:


};

/************************************************************************
 * This file has been generated automatically from                      *
 *                                                                      *
 * src/core/qgstransaction.h                                            *
 *                                                                      *
 * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
 ************************************************************************/