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From Apache Wiki <wikidi...@apache.org>
Subject [Cassandra Wiki] Update of "API" by JoeStump
Date Tue, 25 Aug 2009 15:25:52 GMT
Dear Wiki user,

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

The following page has been changed by JoeStump:
http://wiki.apache.org/cassandra/API

The comment on the change is:
Added notes about SlicePredicates.

------------------------------------------------------------------------------
  
  === SlicePredicate ===
  
+ A `SlicePredicate` is similar to a [http://en.wikipedia.org/wiki/Predicate_(mathematical_logic)
mathematic predicate], which is described as:
+ 
+     Sometimes it is inconvenient or impossible to describe a set by listing all of its elements.
Another useful way to define a set is by specifying a property that the elements of the set
have in common.
+ 
+ `SlicePredicate`'s in Cassandra are described with either a list of `column_names`, a `SliceRange`,
or both.
+ 
  ||'''Attribute'''||'''Type'''||'''Default'''||'''Required'''||'''Description'''||
  ||`column_names`||`list`||n/a||N||A list of column names to retrieve. This can be used similar
to Memcached's "multi-get" feature to fetch N known column names. For instance, if you know
you wish to fetch columns 'Joe', 'Jack', and 'Jim' you can pass those column names as a list
to fetch all three at once.||
  ||`slice_range`||`SliceRange`||n/a||N||A `SliceRange` describing how to range, order, and/or
limit the slice.||

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