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I am a noob coming from a SQL background. Please forgive my SQLness in advance.

Currently working on a new client project in which I need to store mass amounts of data which is fairly simple, but I'm not sure what is the best method for doing this in Couchdb.

This is for employee vehicle tracking. I need to store VIN (Vehicle Identification Number), GPSLat, GPSLong, DateTimeStamp.

The VIN will never change, but will have tons of GPS data associated with it.

In a SQL structure, it would be pretty simple - VIN table, then another relational table for the data.

In a Couchdb key-pair, would you recommend storing the VIN over and over, or do I create 1 VIN as a key-pair and store the GPS data some way? If so, how should I keep storing the GPS data as a key-pair?

Thank you in advance to you experts on key-pair storing.

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You can do it both ways. Couchdb supports linked documents in which you can create a document once and reference it in other documents and then write a view which can emit both the orignal document and the contents of the linked document using include_docs=true.

But since you have a very small data, just one json field, I suggest that you store the field within the document itself since you will have to link the vin id with the document containing rest of the vehicle details anyway.

The linked document strategy is useful when you have lots of fields in the parent document that you want to retrieve with the child document.

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I think it depends on how you want to access the data.

If you regularly access all the linked data, but updates are infrequent, then you could amend the document. Keep in mind though that as you keep updating the same document you have to retrieve it each time, which may get slower as the document could get quite large.

I'd probably store a document for each timestamp. You can use this for very fast access. Your views can support lists so if you have: 

[ {vin as key}, {datestamp}]

You would have very quick access to say all entries for a given vin/date using the startkey/endkey parameters to the view. Similarly you could have a view for the maximum date stamp by vin.

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Thanks guys, so it sounds like the best way for storage is related to how I want to retrieve the data.

Based on the answers above, it sounds like it would be best to store the VIN each time.

Once data is inserted, it won't be updated again.

From a SQL standpoint, my most common query would be something like: SELECT * FROM emp_vehicledata ORDER BY datetimestamp DESC (sometimes I could have a between dates)

So I wouldn't need to go throughout a documents amended revision history to get a specific set of dates, it looks like a new key-pair with the VIN is best for every entry.

Am I understanding Couchdb storage correctly? Thanks again

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I think you do. I'd have two types of data: type1 is vehicledata, type2 is positiondata - which contains a vin. I'd then have a view that uses [vin, timestamp] (use this if your SQL equivalent would have a WHERE clause on the vin) or [timestamp [, vin]] if you really just want data by vin. I've rarely seen a benefit of linked lists, but would setup the keys on my vehicles so that I can either access the document directly knowing the vin, or have a second view, keyed by vin only where I would get the data for the vehicle.

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