Permanent User Defined Function (UDF) in Hive

• We can create a temporary function in hive and use the function in our query, however this is valid till the current session is alive. 
• If we want the function to be permanent we need to create a permanent function.

Steps involved to create a permanent function in Hive

1) Store the JAR file in hdfs location instead of local. If we have already created local function we might have to use a new function name 

2) Create permanent function in hive shell

 hive> CREATE FUNCTION MASK AS 'hiveudf.PI' 

  using JAR 'hdfs://localhost:8020/user/cloudera/Mask.jar'; 

 in the hive shell 

Note: When the function is created, it moves the JAR file from HDFS to local system