Query Cloudant NoSQL database with respect to time intervals

Question

I'am working on Cloudant NoSQL database, the data is received every 15 seconds, so in every 5 mins there will be 20 documents on the database.

I need to get documents which have a difference in timestamp of five minutes for example, Document with time stamp:"2017-03-14 T 18:21:58" and Document with time stamp:"2017-03-14 T 18:26:58" and so on...

Sample document:

xpqz xpqz · Accepted Answer · 2017-03-15T08:34:05

Make a view keyed on the timestamp. I interpret your question as "get all 20 documents sharing a particular timestamp". If that's the case you can get away with not parsing the timestamp:

function(doc) {
    if (doc && doc.timestamp) {
        emit(doc.timestamp, 1)
    }
}

You can now query the view:

% curl 'https://USER:[email protected]/DATABASE/_design/DDOC/view/VIEWNAME?key=TIMESTAMP&include_docs=true&limit=20'

Substitute the uppercase bits to the relevant names and parameters for your system.

If you need finer granularity for your query (time series style), there is an old-but-useful blog from one of the Cloudant founders on the topic here: https://cloudant.com/blog/mapreduce-from-the-basics-to-the-actually-useful/

Query Cloudant NoSQL database with respect to time intervals

1 Answers