[BUG] PIT Search Response Missing Some Metadata Information Like `_score`, `_maxscore`

by ADMIN 87 views

[BUG] PIT search response missing some metadata information like _score, _maxscore

In this article, we will discuss a bug that occurs when using PIT (Point-in-Time) search in OpenSearch SQL. The bug causes the response to miss some metadata information like _score and _maxscore. We will go through the steps to reproduce the bug, the expected behavior, and the environment in which the bug occurs.

What is the Bug?

When using PIT search, the response misses some metadata information like _score and _maxscore. This bug can cause issues when trying to analyze the results of a query.

How Can One Reproduce the Bug?

To reproduce the bug, follow these steps:

Step 1: Add Documents

First, add some documents to the index using the following POST request:

POST /test/_doc
{"index": {"_index": "test"}}
{"col1": 123}
{"index": {"_index": "test"}}
{"col1": 124}
{"index": {"_index": "test"}}
{"col1": 125}

This will create three documents in the test index with the col1 field containing the values 123, 124, and 125.

Step 2: Submit Query

Next, submit the following query to retrieve the documents:

source=test  |  fields col1, _score, _maxscore

This query will return the documents with the col1 field, as well as the _score and _maxscore metadata fields.

Step 3: Change Index Setting

To trigger PIT search, change the index setting max_result_window to a value less than the query.size_limit. Note that after merging the PR https://github.com/opensearch-project/sql/pull/3623, we won't have query.size_limit limit from the source, it will always use PIT search unless having limit push down.

PUT /test/_settings
{
  "index": {
    "max_result_window": 1
  }
}

This will set the max_result_window to 1, which is less than the query.size_limit.

Step 4: Submit Query Again

Finally, submit the query again to retrieve the documents:

source=test  |  fields col1, _score, _maxscore

This time, the response will be incorrect, with all _score and _maxscore columns being null.

What is the Expected Behavior?

The expected behavior is that the response should include the _score and _maxscore metadata fields, even when using PIT search.

What is Your Host/Environment?

  • OS: [e.g. iOS]
  • Version: [e.g. 22]
  • Plugins: [e.g. PIT search plugin]

Do You Have Any Screenshots?

If applicable, add screenshots to help explain the problem.

Do You Have Any Additional Context?

Add any other context about the problem.

In conclusion, the bug causes the response to miss some metadata information like _score and _maxscore when using PIT search. To reproduce the bug, follow the outlined above. The expected behavior is that the response should include the _score and _maxscore metadata fields, even when using PIT search.

To troubleshoot this issue, you can try the following:

  • Check the index setting max_result_window to ensure it is set correctly.
  • Verify that the query.size_limit is not being applied.
  • Check the PIT search configuration to ensure it is set up correctly.

Fix PIT search response missing metadata information

In our previous article, we discussed a bug that occurs when using PIT (Point-in-Time) search in OpenSearch SQL. The bug causes the response to miss some metadata information like _score and _maxscore. In this article, we will provide a Q&A section to help you better understand the issue and its implications.

Q: What is the bug?

A: The bug causes the response to miss some metadata information like _score and _maxscore when using PIT search.

Q: How can I reproduce the bug?

A: To reproduce the bug, follow these steps:

  1. Add documents to the index using the POST request.
  2. Submit the query to retrieve the documents.
  3. Change the index setting max_result_window to a value less than the query.size_limit.
  4. Submit the query again to retrieve the documents.

Q: What is the expected behavior?

A: The expected behavior is that the response should include the _score and _maxscore metadata fields, even when using PIT search.

Q: What is the impact of this bug?

A: The impact of this bug is that the response will be incorrect, with all _score and _maxscore columns being null.

Q: How can I troubleshoot this issue?

A: To troubleshoot this issue, you can try the following:

  • Check the index setting max_result_window to ensure it is set correctly.
  • Verify that the query.size_limit is not being applied.
  • Check the PIT search configuration to ensure it is set up correctly.

Q: Are there any related issues?

A: Yes, there are related issues:

Q: How can I fix this issue?

A: To fix this issue, you can try the following:

  • Update the index setting max_result_window to a value greater than or equal to the query.size_limit.
  • Verify that the PIT search configuration is set up correctly.

Q: What is the commit message for this fix?

A: The commit message for this fix is: Fix PIT search response missing metadata information

Q: Where can I find the API documentation for PIT search?

A: You can find the API documentation for PIT search at: PIT Search API

Q: Where can I find the code snippets for PIT search?

A: You can find the code snippets for PIT search at: PIT Search Code

Q: Where can I find the code snippets for index settings?

A: You can find the code snippets for index settings at: Index Settings Code

In conclusion, the bug causes the response to miss some metadata information like _score and _maxscore when using PIT search. We hope this Q&A section has helped you better understand the issue and its implications. If you have any further questions, please don't hesitate to ask.