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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "Hive/Tutorial" by briangrossman
Date Thu, 08 Jul 2010 23:00:59 GMT
Dear Wiki user,

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

The "Hive/Tutorial" page has been changed by briangrossman.
The comment on this change is: requests for clarification.
http://wiki.apache.org/hadoop/Hive/Tutorial?action=diff&rev1=28&rev2=29

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

  === Complex Types ===
  Complex Types can be built up from primitive types and other composite types using:
  
-  * Structs: the elements within the type can be accessed using the DOT (.) notation. For
example, for a column c of type STRUCT {a INT; b INT} the a field is accessed by the expression
a.c
+  * Structs: the elements within the type can be accessed using the DOT (.) notation. For
example, for a column c of type STRUCT {a INT; b INT} the a field is accessed by the expression
a.c '''shouldn't this be ''c.a''?'''
   * Maps (key-value tuples): The elements are accessed using ['element name'] notation. For
example in a map M comprising of a mapping from 'group' -> gid the gid value can be accessed
using M['group']
   * Arrays (indexable lists): The elements in the array have to be in the same type. Elements
can be accessed using the [n] notation where n is an index (zero-based) into the array. For
example for an array A having the elements ['a', 'b', 'c'], A[1] retruns 'b'.
  
@@ -86, +86 @@

   * Relational Operators - The following operators compare the passed operands and generate
a TRUE or FALSE value depending on whether the comparison between the operands holds or not.
  
  ||'''Relational Operator''' ||'''Operand types''' ||'''Description''' ||
+ || ''???'' ||||surely there are operators for equality and lack of equality? ||
  ||A < B ||all primitive types ||TRUE if expression A is  less than expression B otherwise
FALSE ||
  ||A <= B ||all primitive types ||TRUE if expression A is less than or equal to expression
B otherwise FALSE ||
  ||A > B ||all primitive types ||TRUE if expression A is greater than expression B otherwise
FALSE ||

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