ElasticSearch - Delete documents by specific field

Question

This seemingly simple task is not well-documented in the ElasticSearch documentation:

We have an ElasticSearch instance with an index that has a field in it called sourceId. What API call would I make to first, GET all documents with 100 in the sourceId field (to verify the results before deletion) and then to DELETE same documents?

Answer 1

POST /my_index/_delete_by_query?conflicts=proceed&pretty
{
  "query": {
    "match_all": {}
  }
}

Delete all the documents of an index without deleting the mapping and settings: See: https://opster.com/guides/elasticsearch/search-apis/elasticsearch-delete-by-query/