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sortingnullopensearch

If all fields for a column are null, OpenSearch does not include that field, and so sorting on that field fails

When adding sorting configuration for data in OpenSearch, I came across a situation where the data's field that I want to sort on had only null values. OpenSearch return an error that says [query_shard_exception] Reason: No mapping found for [MY_NULL_FIELD] in order to sort on. That being said, if I add ONE value, then the sort functions as expected. Is there a way around this?

Solution

  • If field values are all null in all documents, the field probably does not exist in the mapping. Using unmapped_type in the sort query should work.

    {
  "sort": [
    {
      "some_missing_field": {
        "order": "asc",
        "unmapped_type" : "long"
      }
    }
  ]
}