Mongodb Aggregation query Optimization

[steevej (Steeve Juneau)]

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Aggreagtion query optimization

Hi Team, I have the below aggreagtion query where I am using $addField $lookup and $unwind and I have the Index which is using but it still takes more than 13 Seconds to execute this query. Can anyone let me know why this is taking so much time for this query and the possible ways to optimize this? db.getCollection('booked-slot').aggregate([{"$match":{"facility":ObjectId("63ee2e8458b6fd9eb66511ce")}},{"$addFields":{"userId":{"$cond":{"if":{"$eq":["$participant.isPrimary",true]},"then":"$part…