Data nodes can depend on one another in a parent-to-child relationship or via references in operations. (See Dependencies between data nodes.) 

In both cases, changes to the referenced nodes (the parent node or a data node referenced by an operation) invalidate the result table of the child nodes.

The figure above shows a set of 11 data nodes with dependencies. The dependencies cannot be circular. Hence, the dependencies result in a directed, acyclic graph.

When some ancestor, e.g., data node X changes, then all its descendants are invalid. They are not automatically recalculated. In the TIS 6.0 Editor, such nodes are marked with the recalculation symbol ().

All ancestors of a data node, e.g., data node Y, are recalculated automatically whenever a recalculation is triggered by the data node. This trigger can be

(If the recalculation modality is set to fixed, then the data node cannot be recalculated.)