Partial updates in Elasticsearch - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a partial update in Elasticsearch?

A partial update changes only specific fields of a document without replacing the entire document. It saves time and resources by updating just what is needed.

beginner

How do you perform a partial update using the Elasticsearch API?

You use the _update endpoint with a doc field containing only the fields you want to change.

intermediate

What happens if the field you want to update does not exist in the document?

Elasticsearch adds the new field to the document during the partial update.

intermediate

Can you use scripts in partial updates? Why would you use them?

Yes, scripts let you modify fields dynamically, like incrementing a number or appending to a list, during a partial update.

beginner

What is the difference between a full document update and a partial update in Elasticsearch?

A full update replaces the entire document, while a partial update changes only specified fields, keeping the rest unchanged.

Which Elasticsearch endpoint is used for partial updates?

A /_search

B /_delete

C /_update

D /_index

The /_update endpoint is specifically designed for partial updates.

What must you include in the request body to update only specific fields?

A The full document

B A <code>doc</code> object with fields to update

C Only the document ID

D A <code>query</code> object

The doc object holds the fields you want to change in a partial update.

If a field does not exist in the document, what does a partial update do?

A Throws an error

B Deletes the document

C Ignores the field

D Adds the new field to the document

Elasticsearch adds new fields during partial updates if they don't exist.

Why might you use a script in a partial update?

A To dynamically modify field values

B To delete the document

C To replace the whole document

D To search documents

Scripts allow dynamic changes like incrementing or appending during updates.

What is a benefit of partial updates over full document updates?

A They reduce network and processing load

B They require sending the entire document

C They are slower

D They delete old fields automatically

Partial updates send only changed fields, saving bandwidth and processing.

Explain how to perform a partial update in Elasticsearch and why it is useful.

Think about updating only what you need.

Describe the role of scripts in partial updates and give an example use case.

Scripts help when simple field replacement is not enough.