Deleting and closing indexes in Elasticsearch - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of closing an index?

You run the following command to close an index named my_index. What is the expected response status in the output?

Elasticsearch

POST /my_index/_close

A {"acknowledged":true}

B {"closed":true}

C {"status":"closed"}

D {"result":"closed"}

💡 Hint

Closing an index returns an acknowledgement from Elasticsearch.

When you close an index in Elasticsearch, the response contains {"acknowledged":true} to confirm the operation succeeded.

❓ Predict Output

intermediate

What happens when deleting a non-existing index?

You try to delete an index named unknown_index that does not exist. What is the typical response status?

Elasticsearch

DELETE /unknown_index

A {"acknowledged":true}

B {"error":{"type":"index_not_found_exception"}}

C {"result":"not_found"}

D {"status":"deleted"}

💡 Hint

Elasticsearch returns an error if the index does not exist when deleting.

Trying to delete a non-existing index returns an error with type "index_not_found_exception".

🧠 Conceptual

advanced

Which statement about closing indexes is true?

Select the correct statement about closing an Elasticsearch index.

A Closed indexes remain writable but are hidden from searches.

B Closing an index frees up disk space by deleting all data.

C Closing an index automatically deletes its mappings.

D A closed index cannot be searched until it is reopened.

💡 Hint

Think about what closing means for index accessibility.

A closed index is not searchable and not writable until reopened, but its data and mappings remain intact.

❓ Predict Output

advanced

What is the output after reopening a closed index?

You closed an index logs_2023 and then reopened it using POST /logs_2023/_open. What is the expected output?

Elasticsearch

POST /logs_2023/_open

A {"acknowledged":true}

B {"opened":true}

C {"result":"opened"}

D {"status":"open"}

💡 Hint

Opening an index returns an acknowledgement similar to closing.

The response to opening an index contains {"acknowledged":true} confirming the operation.

❓ Predict Output

expert

What error occurs when deleting a closed index with aliases?

You have a closed index archive_2022 with an alias archive. You try to delete it using DELETE /archive_2022. What error will Elasticsearch return?

Elasticsearch

DELETE /archive_2022

A {"error":{"type":"index_closed_exception"}}

B {"acknowledged":true}

C {"error":{"type":"illegal_argument_exception","reason":"Cannot delete index with aliases"}}

D {"error":{"type":"alias_not_found_exception"}}

💡 Hint

Deleting an index with aliases is restricted.

Elasticsearch prevents deleting an index that has aliases and returns an illegal_argument_exception with a reason about aliases.