# How to aggregate tags on child nodes?

**URL:** <https://www.ruby-forum.com/t/how-to-aggregate-tags-on-child-nodes/165656>\
**Category:** Rails\
**Created:** [April 16, 2009, 4:45am UTC](https://www.ruby-forum.com/t/how-to-aggregate-tags-on-child-nodes/165656 "2009-04-16T04:45:18Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![raymond](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/c57346/32.png) [@raymond](https://www.ruby-forum.com/u/raymond)\
**Post date:** [April 16, 2009, 4:45am UTC](https://www.ruby-forum.com/t/how-to-aggregate-tags-on-child-nodes/165656/1 "2009-04-16T04:45:18Z")

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Let’s say I have a Recipe model, and it is a parent of the Review  
model. Reviews are entered by users of the system, with one or more  
tags using the acts\_as\_taggable\_on\_steroids plugin (for instance).  
What I’m interested in is how to show _all_ tags for a particular  
Recipe - meaning all tags applied to every child Review of that  
Recipe.

For an example of what I’m talking about, look at this page from this  
fine website:  
[http://97bottles.com/breweries/us/ca/santa-rosa/russian-river-brewing-company/blind-pig-ipa/](http://97bottles.com/breweries/us/ca/santa-rosa/russian-river-brewing-company/blind-pig-ipa/)

They are showing the most popular tags from all Reviews on a  
particular Beer. I’m trying to figure out how to do that.

But I have no idea where to start, since the tagging is such a wily  
concept to me. Any suggestions?