CouchDB has released a simple authentication api but has no in built authentication mechanisms as of yet. The simplest and easiest way to do this is to use an http proxy for authentication. However this has limitations on how much you can restrict access on a per document basis. When CouchDB gets some more support … Read more
Another thing to be aware of is that you can copy files out from under a live database. Given that you may have a possibly large database, you could just copy it OOB from your test/production machine to another machine. Depending on the write load of the machines it may be advisable to trigger a … Read more
It is true that there is no dead-simple answer. There are several patterns however. http://wiki.apache.org/couchdb/View_Snippets#Retrieve_the_top_N_tags. I do not personally like this because they acknowledge that it is a brittle solution, and the code is not relaxing-looking. Avi’s answer, which is to sort in-memory in your application. couchdb-lucene which it seems everybody finds themselves needing eventually! … Read more
The upcoming book by O’Reilly is free to read online: http://books.couchdb.org/relax/ Just install and play around – you can do straight http requests using curl on the command line, or use the built-in web interface called futon. Storing and retrieving data is really easy, the hardest part is thinking in terms of map/reduce-views instead of … Read more
The strengths and weaknesses of the NoSQL databases (and also SQL databases) is highly dependent on your use case. For very large projects, performance is king; but for brand new projects, or projects where time and money are limited, simplicity and time-to-market are probably the most important. For teaching yourself (broadening your perspective, becoming a … Read more
I think there are some essential differences between CouchDB and Couchbase Server that need to be pointed out. I will not write about the advantages of switching from CouchDB to the Couchbase Server because those are described pretty much everywhere (see The Future of CouchDB by Damien Katz or Couchbase vs. Apache CouchDB by Couchbase). … Read more
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Use the official MongoDB BSON lib in the client I have a browser client that generates ObjectIds. I wanted to make sure that I employ the same ObjectId algorithm in the client as the one used in the server. MongoDB has js-bson which can be used to accomplish that. If you are using javascript with … Read more
if “20,000 concurrent writes” means inserts then I would go for CouchDB and use “_changes” api for triggers. But with 20.000 writes you would need a stable sharding aswell. Then you would better take a look at bigcouch And if “20.000” concurrent writes consist “mostly” updates I would go for MongoDB for sure, since Its … Read more
When comparing a BTree index to an SSTable index, you should consider the write complexity: When writing randomly to a copy-on-write BTree, you will incur random reads (to do the copy of the leaf node and path). So while the writes my be sequential on disk, for datasets larger than RAM, these random reads will … Read more