# Parent child for unique index on complex beans **URL:** \ **Category:** Elasticsearch\ **Created:** [January 23, 2013, 10:50am UTC](https://discuss.elastic.co/t/parent-child-for-unique-index-on-complex-beans/10469 "2013-01-23T10:50:41Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Matthew\_Young](https://avatars.discourse-cdn.com/v4/letter/m/a6a055/32.png) [@Matthew\_Young](https://discuss.elastic.co/u/Matthew_Young)\ **Post date:** [January 23, 2013, 10:50am UTC](https://discuss.elastic.co/t/parent-child-for-unique-index-on-complex-beans/10469/1 "2013-01-23T10:50:41Z")
Haven't experimented with ElasticSearch (only read about it)..... Use Neo4j as a store which by default utilizes Lucene to index nodes (and relationships). One thing that has always troubled me is how to \*unique \*index complex beans. Neo4j has nodes and the relationships between them. There is a great SDN module (Spring) that allows domain beans to roll back and forth into Neo4j nodes and parent/child relationships. This is great. I can create a complex bean like Software with a name property (simple, just a string) and an organisation property (complex pointing to another bean). Software might have a name "core" and an organisation (via a Neo4j relation under the covers) with a name "org.matthew". Unique indexes in the SDN exposes Lucene indexes direct (iow, flat documents). So I can put a unique index on Software.name but in my world Software isn't unique just on it's name but rather a combination of name plus the name of the organisation. It is a complex index reacting to changes to the "child". For example, if organisation "org.matthew" becomes "org.young" then the unique index on Software must be checked for duplicates. Or if the organisation "org.matthew" is deleted the request can't be allowed since it might kill the index on Software beans. Each node in Neo4j has a unique id. Could I use the ElasticSearch parent/child stuff to make "complex" \*unique \*indexes? How deep can the parent/child path get? -- ---
**Author:** ![Matthew\_Young](https://avatars.discourse-cdn.com/v4/letter/m/a6a055/32.png) [@Matthew\_Young](https://discuss.elastic.co/u/Matthew_Young)\ **Post date:** [January 24, 2013, 1:14pm UTC](https://discuss.elastic.co/t/parent-child-for-unique-index-on-complex-beans/10469/2 "2013-01-24T13:14:48Z")
Installed ES.... And played around with the examples from: [http://www.spacevatican.org/2012/6/3/fun-with-elasticsearch-s-children-and-nested-documents/](http://www.spacevatican.org/2012/6/3/fun-with-elasticsearch-s-children-and-nested-documents/) If I had read the blog better the first time around I would have noticed the restriction on indexing books (children to authors). Namely that an author (parent) has to be stated in the creation of the book index. Hum. In my case with Software then I have to register Organisation first and that "bean" has to have a "simple" index (iow. no parent/child) then I can register Software with a parent mapping to Organisation. Breaks the case when the Organisation reference in the Software can be null but works in theory otherwise. Surprised that I could delete the author indexes!? And even more surprised when I do GETs that I don't see the mapping information in the response. Weird that the mapping is required to create the book's index but then the associated author index can be deleted. Maybe the parent-child mapping can be made more restrictive? -- ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [July 6, 2017, 2:54am UTC](https://discuss.elastic.co/t/parent-child-for-unique-index-on-complex-beans/10469/3 "2017-07-06T02:54:46Z")