Data Node
A data node is a project component. A list of existing data nodes in a project can be found in a table once the project is opened. See List of Data Nodes for more information about the spreadsheet containing data nodes.
A data node is a container for operations producing or manipulating data. Each operation produces a table or a graph. The last table produced by the sequence of operations is the data node's result table.
A data node can be based on another data node in the same project, its parent node. If it has a parent node, the parent node's result table is the input of the data node.
Each operation is performed by an operator based on some settings and possibly on some input data such as a table produced by a previous operation, the result table of the parent node, a TIS Table, or a file.
A (non-empty) data node hence consists of
a sequence of operations, and
optionally, a reference to another data node in the same project (the parent node).
A data node is empty if it does not reference another data node and its sequence of operations is empty.
If the data node has no parent node, then the first operation of the data node produces a table, e.g., by applying operator Create Table 2.0 or Read TIS Table 8.0. Each subsequent operation takes as part of its input (if any) the table created by its predecessor.
Only the result table of a data node is displayed by the TIS Editor. Tables produced by intermediate operations can be displayed by deactivating subsequent operations (see description of "Operations" tab in Operation).
Data in the result table can be filtered (see Result Table Filter).
Note that only data nodes of the same TIS Project can be referenced as parent node. If another TIS Project's data node is required as input, it has to be saved as TIS Table by operator Write TIS Table 7.0 in the other project, and read into the current project by operator Read TIS Table 8.0.
The Project containing the data node summarizes meta data on a data node, such as row and column count, number of children, in its list of data nodes.
The properties of a data node can be manipulated by clicking on the “Edit properties” button either in the drop-down menu or on the left of the data node name. The same functionality is available within an opened data node.
Properties of a data node that are available for manipulation:
Name: Name of the data node
Description: To add a note which is then shown in the "Description" field of the project's overview on the data nodes
Parent node: Reference to the parent node whose result table serves as input table for this data node
Icon
Text color
Background color
Text format
Additionally, when the data node is opened in Editor, it is possible to add following settings:
Fixed: If this option is ticked, no further changes are possible
Manual: Data node will have to be manually recalculated if it gets dirty by clicking on “Recalculate” button; see Recalculation process between data nodes
TIS Board: Result table of the data node will be available to TIS Board and can be accessed by the Portlet Designer.
Once a (non-empty) data node is opened, the Data Node Homepage shows a sequence of operations taken to create the result table, as well as the result table (see image 2).
From this page, it is possible to add new operations by clicking on “Add operation” button, and also to delete, reorder and/or modify existing operations. See Operation to learn about this tab.
