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From Apache Wiki <wikidi...@apache.org>
Subject [Couchdb Wiki] Trivial Update of "View_Snippets" by SebastianCohnen
Date Sun, 02 May 2010 18:21:08 GMT
Dear Wiki user,

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

The "View_Snippets" page has been changed by SebastianCohnen.
http://wiki.apache.org/couchdb/View_Snippets?action=diff&rev1=37&rev2=38

--------------------------------------------------

  = View Snippets =
  <<TableOfContents()>>
  
- This page collects code snippets to be used in your [[Views]]. They are mainly meant to
help get your head around the map/reduce approach to accessing database content. Keep in mind
that the the Futon web client silently adds group=true to your views.
+ This page collects code snippets to be used in your [[Views]]. They are mainly meant to
help get your head around the map/reduce approach to accessing database content. Keep in mind
that the the Futon web client silently adds ''group=true'' to your views.
  
  
  == Common mistakes ==
  
  When creating a reduce function, a re-reduce should behave in the same way as the regular
reduce. The reason is that CouchDB doesn't necessarily call re-reduce on your map results.
  
- Think about it this way: If you have a bunch of values V1 V2 V3 for key K, then you can
get the combined result either by calling reduce([K,K,K],[V1,V2,V3],0) or by re-reducing the
individual results: reduce(null,[R1,R2,R3],1). This depends on what your view results look
like internally.
+ Think about it this way: If you have a bunch of values ''V1 V2 V3'' for key ''K'', then
you can get the combined result either by calling ''reduce([K,K,K],[V1,V2,V3],0)'' or by re-reducing
the individual results: ''reduce(null,[R1,R2,R3],1)''. This depends on what your view results
look like internally.
  
  
  == Get docs with a particular user id ==
@@ -267, +267 @@

  
  
  == Computing the standard deviation ==
- This example is from the couchdb test-suite. It is '''much''' easier and less complex then
following example ([[#summary_stats|Computing simple summary statistics (min,max,mean,standard
deviation)]]) although it does not calculate min,max and mean (but this should be an easy
exercise).
+ This example is from the couchdb test-suite. It is '''much''' easier and less complex then
following example although it does not calculate min,max and mean (but this should be an easy
exercise).
  
  {{{#!highlight javascript
  // Map

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