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@(@\newcommand{\B}[1]{ {\bf #1} } \newcommand{\R}[1]{ {\rm #1} } \newcommand{\W}[1]{ \; #1 \; }@)@This is dismod_at-20221105 documentation: Here is a link to its current documentation .
The Node Table

Discussion
node_id
node_name
parent
     Children
     Descendant
Example

Discussion
The node table defines a graph that is a tree by specifying the parent for each node. The node table has the following columns:

node_id
This column has type integer and is the primary key for this table. Its initial value is zero, and it increments by one for each row.

node_name
This column has type text and has a different value for every row; i.e., the names are unique and can act as substitutes for the primary key. The names are intended to be easier for a human to remember than the ids.

parent
This column has type integer and is the node_id of the parent for this node. If this node has no parents, parent is null. Note that this is a value for the primary key in this table, but the name of this column does not follow the foreign key naming convention.

Children
The children for node p is the sent of node_id values such that the corresponding parent is equal to p .

Descendant
The set of descendants for a node p is the set children of p , grand children of p , ... .

Example
The file node_table.py contains an example node table.
Input File: omh/table/node_table.omh