beginnerMongoDB — CRUD, Queries & Aggregation Framework
What is the MongoDB Aggregation Framework and how does it compare to SQL?
The Aggregation Framework is MongoDB's data transformation pipeline. Documents flow through sequential stages, each transforming the result. Key stages: $match (WHERE), $group (GROUP BY + aggregates like $sum, $avg), $sort (ORDER BY), $project (SELECT), $limit/$skip (LIMIT/OFFSET), $lookup ($lookup performs a LEFT JOIN to another collection), $unwind (flatten array fields), $addFields (add compute
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