columnar::ContainerId::track Node1 columnar::ContainerId ::track + idName Node3 columnar::ContainerId ::track1 + idName Node1->Node3 Node4 columnar::ContainerId ::track2 + idName Node1->Node4 Node2 columnar::ContainerId ::regularCIBase< xAOD ::TrackParticle, xAOD ::TrackParticleContainer > + isContainerId + regularObjectId + regularColumnAccessorArray + isMutable + perEventRange + perEventId Node2->Node1