Answer
explain() shows how a query is executed, including index usage and performance details. It helps diagnose slow queries.
Quick Answer
explain() shows how MongoDB executes a query - which index was used (IXSCAN vs COLLSCAN), how many documents were examined, execution time, and query plan. Use explain("executionStats") for detailed stats. Essential for performance debugging - if you see COLLSCAN on a frequently run query, you need an index. Always run explain() on new queries in development.
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SugharaIQ Editorial Team
Verified Answer
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Source: SugharaIQ