How to Stream Data from Mongodb?
The Mongo Find(), Return All the Documents in a Collection. I Want to Store Every Document That I Have in My Mongodb in to Another Database. So, I Want to Keep...
The mongo find(), return all the documents in a collection. I want to store every document that I have in my mongodb in to another database. So, I want to keep polling mongodb for single new document, because find().limit(1) would keep returning me the same again and again. I just want mongo to return, all the document one by one. Is it possible? How can this be done?
Edit: I want to just copy every entry in my mongodb instance to another db, not just the latest ones.
2 Answers
Use sort , by default it is a natural sort i.e.:
find().sort({_id:-1}).limit(1)
You will need to store the _id of current document retreived and match it with the next one retreived with the same query, if they are different, you store the document, and also the new _id.
- Better use tailable cursor :
It sounds like Philipp's comment has the answer you're looking for, but to answer the original question:
I wouldn't suggest using a sort on the whole database if you expect your document sizes to be quite large, also a limit would result in horrible performance.
Running a find() operation actually returns a cursor object to you, which you can iterate upon, which is effectively streaming and therefore exactly what you're asking for.
James Sterling reports on renewable energy developments, climate policy, ecological conservation, and green tech innovations around the globe.
