MongoDB: db.collection.isCapped() method

db.collection.isCapped

The db.collection.isCapped() method is used to reports if a collection is a capped collection. Capped collectionsare fixed-size collections that support high-throughput operations that insert and retrieve documents based on insertion order. Capped collections work in a way similar to circular buffers: once a collection fills its allocated space, it makes room for new documents by overwriting the oldest documents in the collection.

Syntax:

db.collection.isCapped()

Returns:

• Returns true if the collection is a capped collection, otherwise returns false.

Sample document in the restaurants collection:

{
  "address": {
     "building": "1007",
     "coord": [ -73.856077, 40.848447 ],
     "street": "Morris Park Ave",
     "zipcode": "10462"
  },
  "borough": "Bronx",
  "cuisine": "Bakery",
  "grades": [
     { "date": { "$date": 1393804800000 }, "grade": "A", "score": 2 },
     { "date": { "$date": 1378857600000 }, "grade": "A", "score": 6 },
     { "date": { "$date": 1358985600000 }, "grade": "A", "score": 10 },
     { "date": { "$date": 1322006400000 }, "grade": "A", "score": 9 },
     { "date": { "$date": 1299715200000 }, "grade": "B", "score": 14 }
  ],
  "name": "Morris Park Bake Shop",
  "restaurant_id": "30075445"
}
.....

Example: MongoDB: db.collection.isCapped() method

Following example describe the indexes on the restaurants database

db.restaurants.isCapped();

Output:

> db.restaurants.isCapped();
false

Retrieve the restaurants data from here

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