This document serves to highlight key breaking changes for our customers. It does not represent the full list of breaking changes. As always, we recommend you test your searches on the new version of Elasticsearch before moving forward.
Elasticsearch 6 has a stand-out breaking change, which is the limitation of only one mapping type per index. This is due to the upcoming removal of mapping types. Before this version all versions of Elasticsearch supported the concept of multiple mapping types, which would let you store different "types" of data in one index. Elastic is removing this feature in ES 7 after announcing its deprecation in ES 6.
This has been the standard recommendation for the best performance in Elasticsearch since its inception. Rather than index multiple types of documents into a single index, simply use one index per document type. Many tools and frameworks supporting Elasticsearch will do this for you automatically.
For those times when it simply doesn't make since to have one document type per index, you can add a dedicated field to the document that declares a document's given type. Then when you query on that index you will simply pass in which type you want the query limited to as well.
After working through the General Solutions above, we recommend you do the following:
There are no specific tricks for this upgrade process, outside of the General Solution listed above. We would simply recommend you follow our traditional process for testing your searches on a new version of Elasticsearch. In short, this involves provisioning a new 6.x cluster and validating it in a development environment. Once it has been validated,
There are no specific tricks for this upgrade process, outside of the General Solution listed above. We would simply recommend you follow our traditional process for testing your searches on a new version of Elasticsearch.