Consider the following documents in a CouchDB: { "name":"Foo1", "tags":["tag1", "tag2", "tag3"], "otherTags":["otherTag1", "otherTag2"] } { "name":"Foo2", "tags":["tag2", "tag3", "tag4"], "otherTags":["otherTag2", "otherTag3"] } { "name":"Foo3", "tags":["tag3", "tag4", "tag5"], "otherTags":["otherTag3", "otherTag4"] ...
Hi, I just wanted to know if there is a fundamental difference between hbase, cassandra, couchdb and monogodb ? In other words, are they all competing in the exact same market and trying to solve the exact same problems. Or they fit best in different scenarios? All this comes to the question, what should I chose when. Matter of taste? ...
I am wondering how to use CouchDB's map/reduce with multiple parameters. For example, if I have teams that have players with ages and genders, I assume I would do this for my map function: "function(doc){ if(doc.team_name) { emit(doc.team_name, doc); } }" However, I am unsure how to write a reduce function to get the oldest m...
Is it possible to use wildcards in views in CouchDB? For example, lets say I have a database that has teams, ages of players, players' averages, and gender of players. However, the players' ages may not be known - they could be from the Dominican Republic or whatnot. So I want to use a view with a map function that can accept not havi...
There appears to be a myriad of NoSQL databases available these days: CouchDB MongoDB Cassandra Hadoop There's also a boundary between these tools and tools such as Redis that work as a memcached replacement. Without hand waving and throwing too many buzz words - my question is the following: How does one intelligently decide which...
Hi, I'm new to Ruby on Rails and I quite like it. Now I'd like to use a CouchDB as storage database and I don't want to implement new RoR schema but instead I want to use RDF schema. Is there any possibility to tell RoR(v3) that a schema is be described by such a file (like this one)? Cheers, Manuel PS: If there is no such feature, y...
how to create "Users" in couchDB (not admin) ..? ...
If You would be Facebook, what nosql db would you use and to do what? I mean the real use cases where a NOSQL makes really an advantage ...
I have problems finding documentation on how to delete a document from CouchDB using CouchPotato. As fare as I know I have to set the property _deleted = true. When I want to get documents that is not deleted, I have tried to add a condition to my class like this: view :item, :key => [:userid, :date], :conditions => 'doc._deleted === ni...
Hi! I am using BigCouch which is a very good implementation of scalable CouchDB cluster. But it has a small problem - it doesn't support CouchDB 1.0-style Security features very well. So it must stay in the Admin Party mode. What are the options to secure a CouchDB instance in the Admin Party mode. Each user should have their own datab...
What are the advantages of using NoSQL databases? I've read a lot about them lately, but I'm still unsure why I would want to implement one, and under what circumstances I would want to use one. ...
I want to perform a LIKE-condition (SQL syntax) in CouchDB. How can this be done? The LIKE-condition will be used to perform auto complete in the browser. I want to write "co" in the input field and get the results Coffee, Couch, CouchDB ect. ...
The quick overview is this: for my web app I can write most of my functionality using CouchApp and CouchDB views, etc. I love the feature of CouchApp that pushes my code up to the server via replication- this makes the deployment cycle very easy. However, to do some arbitrary work not supported in couchdb and works around a few limita...
Hi there, I want to reuse outputted data from a view in another view. like this reduced and grouped data: {"rows":[ {"key":"cool","value":3}, {"key":"einzigartig","value":1}, {"key":"mega","value":1}, {"key":"nice","value":1}, {"key":"spitze","value":1}, {"key":"super","value":2} ]} ...because I want to interchange key <> value so th...
I'm new to CouchDB and want to give it a try. But before I do that I want to know if I can create dynamic database structure in CouchDB. Eg. The user starts on a blank thread and chooses whatever structure he/she wants (eg. title, body and tags and fill them in) When he clicks save thread the database for this is created, maybe nested...
I wonder if MongoDB and CouchDB could work as database for mobile devices? If they both can, which one is better to use for online/offline storage? ...
If my structure looks like this: [{Name: 'A', Depends: []}, {Name: 'B', Depends: ['A']}, {Name: 'C', Depends: ['A']}, {Name: 'D', Depends: ['C']}, {Name: 'E', Depends: ['D','B']}] How would I write the map and reduce functions such that my output is: [{Key: 'A', Value: []}, {Key: 'B', Value: ['A']}, {Key: 'C', Value: ['A']}, {Key: 'D...
Consider the approximated result from map function: "key": "andy", "value" : "Once upon a time", "key": "andy", "value" : "...", "key": "andy", "value" : "They all lived happily ever after.", I would like to create a reduce function that generates: "key":"andy", "value":"Once upon a time ... They all lived happily ever after." ...
In CouchDB you always have to use map reduce to query results. In MongoDB you can their query methods for retrieving data, but they also let you do map-reduce. I wonder, when do I actually need map-reduce? Are those query methods different from map-reduce or are they just wrappers for map-reduce functions? ...
In MongoDB you have a lot of helper methods that do all the basic operations for you: count sort update replace etc... In CouchDB you ahve to write map-reduce for everything by hand for basic operations? ...