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:documentationPath: /plugins/transforms/
:language: en_US
:page-alternativeEditUrl: https://github.com/apache/incubator-hop/edit/master/plugins/transforms/closure/src/main/doc/closure.adoc
= Closure

== Description

This transform was created to allow you to generate a Reflexive Transitive Closure Table for Mondrian.  For more information on how a closure table can help Mondrian gain performance, go here
Technically, this transform reads all input rows in memory and calculates all possible parent-child relationships.  It attaches the distance (in levels) from parent to child.

== Options

[width="90%", options="header"]
|===
|Option|Description
|Transform name|The name that uniquely identifies the transform.
|Parent ID field|The field name that contains the parent ID of the parent-child relationship.
|Child ID field|The field name that contains the child ID of the parent-child relationship.
|Distance field name|The name of the distance field that will be added to the output
|Root is zero|Check this box if the root of the parent-child tree is not empty (null) but zero (0) 
|===