ZODB.Architecture.Storage Interface.commitVersion

Documentation

Store changes made in the source version into the destination version. A VersionCommitError is raised if the source and destination are equal or if the source is an empty string. The destination may be an empty string, in which case the data are saved to non-version storage.

Parameters

Type	Name	Documentation
VersionString	source	The version to be committed. This cannot be an empty string.
VersionString	destination	The version to commit to. This may be an empty string, to commit to the non-version store.
Transaction	transaction

State-dependent

This method is state dependent. It is an error to call this method if the storage is not committing, or if the given transaction is not the transaction given in the most recent tpc_begin.

Undo

If the storage doesn�t support undo, then the old version data may be discarded. If undo is supported, then this operation must be undoable and old transaction data may not be discarded.