[Couchdb Wiki] Update of "HTTP_view_API" by JanLehnardt

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The "HTTP_view_API" page has been changed by JanLehnardt.
The comment on this change is: add include_docs performance trade off.
http://wiki.apache.org/couchdb/HTTP_view_API?action=diff&rev1=48&rev2=49

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  If a view contains both a map and reduce function, querying that view will by default return the result of the reduce function. The result of the map function only may be retrieved by passing ''reduce=false'' as a query parameter.
  
- The ''include_docs'' option will include the associated document. However, the user should keep in mind that there is a race condition when using this option. It is possible that between reading the view data and fetching the corresponding document that the document has changed. If you want to alleviate such concerns you should emit an object with a _rev attribute as in ''emit(key, {"_rev": doc._rev})''. This alleviates the race condition but leaves the possibility that the returned document has been deleted (in which case, it includes the ''"_deleted": true'' attribute).
+ The ''include_docs'' option will include the associated document. However, the user should keep in mind that there is a race condition when using this option. It is possible that between reading the view data and fetching the corresponding document that the document has changed. If you want to alleviate such concerns you should emit an object with a _rev attribute as in ''emit(key, {"_rev": doc._rev})''. This alleviates the race condition but leaves the possibility that the returned document has been deleted (in which case, it includes the ''"_deleted": true'' attribute). '''Note''': ''include_docs'' will cause a single document lookup per returned view result row. This adds significant strain on the storage system if you are under high load or return a lot of rows per request. If you are concerned about this, you can emit the full doc in each row; this will increase view index time and space requirements, but will make view reads optimally fast.
+ 
  
  The ''inclusive_end'' option controls whether the ''endkey'' is included in the result. It defaults to true.