I want to delete all the collections from my db which are not used for long time. Is there any why i can check when the particular collection was last used?
-
Do you have any field in your records, which is updated with every update and insert?Shrabanee– Shrabanee2016-06-10 08:28:23 +00:00Commented Jun 10, 2016 at 8:28
Add a comment
|
1 Answer
It depends what you mean by 'last used'. If you mean the last time a document was inserted into the collection then you could do this by converting the ObjectId of the last inserted document into a date. The following query should return the date the last document was inserted:
db.<collection_name>.findOne({},{_id:1})._id.getTimestamp()
the findOne query will return documents in natural order, therefore if you input no query criteria ('{}') then it will return the most recently inserted document. You can then get the _id field and call the getTimestamp() function
I'm not sure if there is any way to reliably tell when a collection was last queried. If you're running your database with profiling enabled then there might be entries in the db.system.profile collection, or in the oplog.
answered Jun 10, 2016 at 8:20
