Elasticsearch Learning Elasticsearch with kibana Modify your elasticsearch data


Example

Elasticsearch provides data manipulation & data searching capabilities in almost real time. under this example, we have update, delete & batch processing operations.

  • Updating the same document. Suppose we have already indexed a document on /car/external/1 . Then running the command for indexing the data replaces the previous document.
PUT /car/external/1?pretty
{
  "name": "Tata Nexa"
}

previous car document at id 1 with name "Tata Nexon" will be updated with new name "Tata Nexa"

  • indexing the data with explicit Id
POST /car/external?pretty
{
  "name": "Jane Doe"
}

for indexing the document without an Id we use POST verb instead of PUT verb. if we don't provide an Id, elasticsearch will generate a random ID and then use it to index the document.

  • Updating the previous document at an Id partially.
POST /car/external/1/_update?pretty
{
  "doc": { "name": "Tata Nex" }
}
  • updating the document with additional information
POST /car/external/1/_update?pretty
{
  "doc": { "name": "Tata Nexon", "price": 1000000 }
}
  • updating the document using simple scripts.
POST /car/external/1/_update?pretty
{
  "script" : "ctx._source.price += 50000"
}

ctx._source refers to the current source document that is about to be updated. Above script provides only one script to be updated at the same time.

  • Deleting the document
DELETE /car/external/1?pretty

Note: deleting a whole index is more efficient than deleting all documents by using Delete by Query API

Batch Processing

Apart from indexing updating & deleting the document, elasticsearch also provides provides the ability to perform any of the above operations in batches using the _bulk API.

  • for updating multiple documents using _bulk API
POST /car/external/_bulk?pretty
{"index":{"_id":"1"}}
{"name": "Tata Nexon" }
{"index":{"_id":"2"}}
{"name": "Tata Nano" }
  • for updating & deleting the documents using _bulk API
POST /car/external/_bulk?pretty
{"update":{"_id":"1"}}
{"doc": { "name": "Tata Nano" } }
{"delete":{"_id":"2"}}

If an operation fails, bulk API doesn't stop. It executes all the operations & finally returns report for all the operations.