Mar 21 – 27, 2009
Europe/Prague timezone

ROOT: Support For Significant Evolutions of the User Data Model

Mar 23, 2009, 5:30 PM
Club E (Prague)

Club E


Prague Congress Centre 5. května 65, 140 00 Prague 4, Czech Republic
oral Event Processing Event Processing


Mr Philippe Canal (Fermilab)


One of the main strength of ROOT I/O is its inherent support for schema evolution. Two distinct modes are supported, one manual via a hand coded Streamer function and one fully automatic via the ROOT StreamerInfo. One draw back of the Streamer function is that they are not usable by TTrees in split mode. Until now, the automatic schema evolution mechanism could not be customized by the user and the only mechanism to go beyond the default rules was to revert to using the Streamer Function. In ROOT 5.22/00, we introduced a new mechanism which allows user extensions of the automatic schema evolution that can be used in object-wise, member-wise and split modes. This presentation will describe the myriads of possibility ranging from the simple assignment of transient members to the complex reorganization of the user's object model.
Presentation type (oral | poster) oral

Primary author

Mr Philippe Canal (Fermilab)


Presentation materials