To check if a collection is capped, use the isCapped() method.
About this Task
Generally, TTL (Time To Live) indexes offer better performance and more flexibility than capped collections. TTL indexes expire and remove data from normal collections based on the value of a date-typed field and a TTL value for the index.
Capped collections serialize write operations and therefore have worse concurrent insert, update, and delete performance than non-capped collections. Before you create a capped collection, consider if you can use a TTL index instead.
Before you Begin
Create a non-capped collection and a capped collection:
db.createCollection("nonCappedCollection1") db.createCollection("cappedCollection1", { capped: true, size: 100000 } )
Steps
To check if the collections are capped, use the isCapped() method:
db.nonCappedCollection1.isCapped() db.cappedCollection1.isCapped()
false true