mongodb query_error ai_generated true

Unexpected results: sparse index not matching null fields

ID: mongodb/sparse-index-null

Also available as: JSON · Markdown
80%Fix Rate
84%Confidence
3Evidence
2023-01-01First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
7 active — — —

Root Cause

Sparse index excludes documents with null/missing field from queries.

generic

Workarounds

  1. 90% success Use partial index with explicit filter expression instead of sparse
  2. 85% success Document sparse index behavior for application developers

Dead Ends

Common approaches that don't work:

  1. Convert sparse to non-sparse index 72% fail

    Much larger index for sparse fields

  2. Remove sparse index 68% fail

    Loses index for existing values