ElasticSearch version changes
Elasticsearch is a distributed document storage. Elasticsearch does not store information as rows of column data, but instead stores complex data structures that have been serialized into JSON documents. When there are multiple Elasticsearch nodes in the cluster, the stored documents will be distributed throughout the cluster and can be accessed immediately from any node.
The above is the introduction of ES7.x official documents. In my previous ES article, it was based on the ES6.x version. Therefore, in order to make the format easier to remember, a comparison was made with relational databases.
| Relational Database | ElasticSearch |
|---|---|
| database | Index |
| table | Type |
| Row | Documents |
| Column | Field Feilds |
But in ES7.x it is clearly stated that there is no concept of type.
- 5.x supports multiple types
- 6.x can only have one type
- 7.x will remove the concept of type without type
The absence of type does not completely abolish the concept of type. But no longer distinguish between types. Because all type=_doc in ES7.x. Therefore, the type is no longer distinguished, that is, there is no need to create the type by yourself during the indexing process.
