What are the system views you should always create with CouchDB?

Once you have created a database, you will start using it from your application and monitoring it will become important. Of course, you can use some existing UI of Cloudant or Futon. However, it is good to have some simple views that will quickly help you detect a potential issue. So far, I have used 3 views to get:

• the number of documents having conflicts,
• the number of documents having deleted conflicts,
• the number of documents by type.

Here is the design document to create these views:

   {
     "language": "javascript",
      "views":
      {
        "conflicts": {
          "map": "function(doc) { if (doc._conflicts)  emit(null, doc._rev) }"
        },"deleted_conflicts": {
          "map": "function(doc) { if (doc._deleted_conflicts)  emit(null, doc._rev) }"
        },"documents": {
          "reduce" : "_sum",
          "map": "function(doc) { if (doc.type)  { emit(doc.type, 1) } else { emit('other',1) }}"
        } 
     }
   }

Of course, replace the attribute type with the attribute you use to distinguish between documents.