---
title: "How to use virtual entity?"
url: "https://openforis.support/questions/1953/how-to-use-virtual-entity"
tags: ["collect"]
status: "answered"
score: 0
answer_count: 1
asked: "2018-09-17T17:50:34"
last_activity: "2018-09-21T04:12:47"
source: "Open Foris Support - Q&A Forum"
license: "Copyright Open Foris, 2026. Some rights reserved under creative commons license."
---

# How to use virtual entity?

Asked by Rajkumar on 2018-09-17

Hi All,
OFT has added virtual entity tools. By the name this table contains calculated value within it. I tried to use it but unable to use it. How can we use it, can any one give an example on it? Thank you very much.


## Answer (score 0, by Stefano (OF) on 2018-09-21)

Link: https://openforis.support/questions/1953/how-to-use-virtual-entity/1956

Dear Rajkumar,  
The "Virtual entity" is still an experimental feature and it's not working yet, we will improve it soon.  
Basically the "rows" in the entity will be generated according to the "Generator expression". You have to define attributes in the virtual entity that will "match" the result of the expression.   
The entity will be included only in data export.  
E.g. suppose that you have an entity called `tree` and you want to create a virtual entity at the same level called `acacia_tree` (with the same attributes as `tree`) that filters the `tree` entity including only trees with acacia species. The generator expression will be: `tree[species='ACACIA']`  
Let us know if it fits your needs.  
Many thanks,  
Open Foris Team