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The "Counters" page has been changed by SylvainLebresne:
http://wiki.apache.org/cassandra/Counters?action=diff&rev1=12&rev2=13

  == Technical limitations ==
  
    * If a write fails unexpectedly (timeout or loss of connection to the 
coordinator node) the client will not know if the operation has been performed. 
A retry can result in an over count 
[[https://issues.apache.org/jira/browse/CASSANDRA-2495|CASSANDRA-2495]].
-   * Counter removal is intrinsically limited. For instance, if you issue very 
quickly the sequence "increment, remove, increment" it is possible for the 
removal to be lost (if for some reason the remove happens to be the last 
received messages). Hence, removal of counters is provided for definitive 
removal, that is when the deleted counter is not increment afterwards. Note 
that if you need to reset a counter, you can read its ''value'' and insert 
''-value''. 
+   * Counter removal is intrinsically limited. For instance, if you issue very 
quickly the sequence "increment, remove, increment" it is possible for the 
removal to be lost (if for some reason the remove happens to be the last 
received messages). Hence, removal of counters is provided for definitive 
removal only, that is when the deleted counter is not increment afterwards. 
Note that if you need to reset a counter, you can read its ''value'' and insert 
''-value''. 
  
  == Further reading ==
- See [[https://issues.apache.org/jira/browse/CASSANDRA-1072|CASSANDRA-1072]] 
and especially the 
[[https://issues.apache.org/jira/secure/attachment/12459754/Partitionedcountersdesigndoc.pdf|design
 doc]] for further information about how this works internally.
+ See [[https://issues.apache.org/jira/browse/CASSANDRA-1072|CASSANDRA-1072]] 
and especially the 
[[https://issues.apache.org/jira/secure/attachment/12459754/Partitionedcountersdesigndoc.pdf|design
 doc]] for further information about how this works internally (but note that 
some of the limitation fixed in these technical documents have been fixed since 
then, for instance all consistency level '''are''' supported, for both reads 
and writes).
  

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