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Use the all positional operator in MongoDB to update all elements in an array

For a full overview of MongoDB and all my posts on it, check out my overview.

MongoDB provides a special update operator $[] to apply an update operation to all elements in an array belonging to matching documents.

With the following data inserted into a collection called games:

db.games.insertMany(
	{
		name: "Genshin Impact",
		reviewScores: [8, 6, 9, 5]
	},
	{
		name: "Factorio",
		reviewScores: [7, 7, 10, 8]
	},
	{
		name: "Bloodborne",
		reviewScores: [9, 8, 9, 9]
	}
)

For every game that does NOT have a score of 10 in its reviews, increase all the review scores by 1.

db.games.updateMany(
	{ reviewScores: { $ne: 10 } },
	{ $inc: { "reviewScores.$[]": 1 } }
)

Use the find method to read all the data back out to view the results:

{
	name: "Genshin Impact",
	reviewScores: [9, 7, 10, 6]
},
{
	name: "Factorio",
	reviewScores: [7, 7, 10, 8]
},
{
	name: "Bloodborne",
	reviewScores: [10, 9, 10, 10]
}

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