MongoDB: Search in array -

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i have field in mongodb collection like:
{ place = ['london','paris','new york'] } need query return particular entry of array, specific character occurs. example, want search terms having letter 'o'(case-insensitive) in them. should return 'london' , 'new york'.
tried db.cities.find({"place":/o/i}), returns whole array.

you'll need $unwind using aggregate query, match.

db.cities.aggregate([ { $unwind:'$place' }, { $match: { place : {$regex: /o/i } } } ])

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