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From Apache Wiki <wikidi...@apache.org>
Subject [Couchdb Wiki] Update of "HttpGetUuids" by JasonSmith
Date Mon, 16 Apr 2012 12:04:34 GMT
Dear Wiki user,

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The "HttpGetUuids" page has been changed by JasonSmith:
http://wiki.apache.org/couchdb/HttpGetUuids?action=diff&rev1=8&rev2=9

Comment:
Correct the UUID algorithm label

  
   * {{{random}}}: 32 hex characters generated completely at random.
  
-  * {{{sequence}}}: 26 hex character random prefix, followed by 6 hex characters of sequence,
which is incremented by random amounts. When the 6 character sequence overflows, a new random
prefix is chosen. There are no guarantees of ordering, but most inserted documents will be
sequentially ordered. This improves insert speed as most B-tree edits do not happen randomly.
Also, if the documents are likely to be accessed sequentially, this improves access speeds.
+  * {{{sequential}}}: 26 hex character random prefix, followed by 6 hex characters of sequence,
which is incremented by random amounts. When the 6 character sequence overflows, a new random
prefix is chosen. There are no guarantees of ordering, but most inserted documents will be
sequentially ordered. This improves insert speed as most B-tree edits do not happen randomly.
Also, if the documents are likely to be accessed sequentially, this improves access speeds.
  
   * {{{utc_random}}}: First 14 hex characters are microseconds since Jan 1, 1970 (Unix epoch),
followed by 18 random hex characters.
  

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