[Couchdb Wiki] Update of "Tags_inside_documents" by JoanTouzet

[Apache Wiki <wi...@apache.org>]

Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Couchdb Wiki" for change notification.

The "Tags_inside_documents" page has been changed by JoanTouzet:
https://wiki.apache.org/couchdb/Tags_inside_documents?action=diff&rev1=3&rev2=4

- <<Include(EditTheWiki)>>
+ This content has been migrated to our [[http://docs.couchdb.org/en/stable/ddocs/views/collation.html|official documentation].
  
- Tags are stored as a list of strings inside the document:
- 
- {{{
- {
-  "_id":"123BAC",
-  "_rev":"946B7D1C",
-  "type":"post",
-  "subject":"I like Planktion",
-  "author":"Rusty",
-  "created":"2006-08-15T17:30:12Z-04:00",
-  "body":"I decided today that I don't like baseball. I like plankton.",
-  "tags":["plankton", "baseball", "decisions"]
- }
- }}}
- 
- == CouchDB Views ==
- 
- '''Retrieve all tags with their counts:'''
- 
- ''map''
- 
- {{{
- function(doc) {
-   if (doc.type == 'post' && doc.tags) {
-     doc.tags.forEach(function(tag) {
-       emit(tag, 1);
-     });
-   }
- }
- }}}
- 
- ''reduce''
- 
- {{{
- function(keys, values) {
-   return sum(values);
- }
- }}}
- 
- Note: when retrieving data from this view, if the results are reduced to a single row, you may need to use the ?group=true option to get counts reduced by tag.  This may be a feature in version 0.8.0 and forward? see HttpViewApi.
- 
- '''Retrieve documents by a specific tag:'''
- 
- ''map''
- 
- {{{
- function(doc) {
-   if (doc.type == 'post' && doc.tags) {
-     doc.tags.forEach(function(tag) {
-       emit(tag, doc);
-     });
-   }
- }
- }}}
-