hive UDF 学习 0.9.0

今天看下hive到什么版本了，目前最搞版本是0.9.0
1、先看了下udf更新内容，原文如下

A java class and method often exists to handle the exact function a user would like to use in hive. Rather then having to write a wrapper UDF to call this method, the majority of these methods can be called using reflect udf. Reflect uses java reflection to instantiate and call methods of objects, it can also call static functions. The method must return a primative type or a type that hive knows how to serialize.
SELECT reflect("java.lang.String", "valueOf", 1),
       reflect("java.lang.String", "isEmpty"),
       reflect("java.lang.Math", "max", 2, 3),
       reflect("java.lang.Math", "min", 2, 3),
       reflect("java.lang.Math", "round", 2.5),
       reflect("java.lang.Math", "exp", 1.0),
       reflect("java.lang.Math", "floor", 1.9)
FROM src LIMIT 1;

1	true	3	2	3	2.7182818284590455	1.0

这个版本不需要用户写udf要集成UDF接口，任何方法都可以通过反射来实现UDF功能
2、roadmap说明了些新特性，重点看了几个自己感兴趣的Implement Indexing in Hive，hive中将支持索引，jira状态是close，应该最新的版本中就会体现，应该在0.10.0吧

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