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Which NoSQL flavor of database technology will allow me sequential access to query data?

Here is a description of what I mean by sequential access:

Imagine there is some data being pumped into the database, and your application's requirement is to process it serially.

I intend to query some documents based on some condition. I issue a query against the instance and get a response that has a finite number of records and a sequence identifier (in case I am interested in getting the next set of similar data - pertaining to the same query).

Hence to retrieve, the next set, I issue the same query and, this time, I'd pass this sequence id along with it. This specifically tells the db engine to get newer records after that sequence. So the db engine, based on some algorithm will give me fresh set of records/data/documents.

Which opensource db engine does this?

The use case is something like my app:

  1. open connection
  2. queries data
  3. caches data
  4. closes connection
  5. processes data
  6. opens connection
  7. queries with previously obtained sequence id
  8. ...repeats...
  • What operating system does it need to run on? – Undo Jun 15 '16 at 13:42
  • Explanation by Andriy M: "I think what is meant is some kind of an autoincrement key that could be (1) generated for new data, (2) returned in the results and (3) used in querying another portion of data. (I don't think ability to return a sorted result set is necessary for this specific problem although that would certainly not hurt.) That's certainly a trivial thing in the SQL world, and the question may be asking whether an open-source NoSQL product exists that has this feature." – Nicolas Raoul Jun 16 '16 at 7:58
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You can do that with MongoDB:

  1. Fetch first 100 from cursors
  2. close connection
  3. open connection
  4. create new cursor, skip 100 and fetch the next 100

Skipping is done via https://docs.mongodb.com/manual/reference/method/cursor.skip

MongoDB is open source.

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I would think that technically, they all do. It comes down to writing your queries correctly to access the data-set you need, and in the right order - via sorting the result, for example.

  • Please give the syntax for a NoSQL database of your choice, thanks! – Nicolas Raoul Jun 16 '16 at 7:59

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