Search code examples
elasticsearchschemaelastic-stack

relation between shcema on read and field extraction in read time

I'm researching about ELK Stack and there are two concepts that I'm not sure how they are related to each other.

  1. Schema on reading: I know it makes you able to decide about data structure in reading time
  2. Extracting data in reading time: these can help you to extract some fields in query time and not in index time. also, there is a runtime field which is defined by ELK Elasticsearch as 'A runtime field is a field that is evaluated at query time.' so it can be used for reading time field extraction.

my question is that what is the relation between reading time field extraction and schema on reading and how runtime fields can stand.

Solution

  • schema on read is a concept, runtime fields are the underlying part of the technology that allows that concept to happen

    from https://www.elastic.co/blog/whats-new-elasticsearch-7-11-0-schema-on-read-is-here;

    We call the feature that delivers schema on read runtime fields