Questions about Hive UDF cache under the hood

["r7raul1984@163.com" <r7...@163.com>]

  Hi everyone, 
         Consider the sql : 
            SELECT thumbnail( product_ image ) 
            FROM advert i sements 
            WHERE product_name = ‘ Brownie’ ; 
     The  product_ image field is a reference to a multi-megabyte image object. The thumbnail method reads in this object, and produces a small version of the image. Reading and processing the object can be quite time-consuming, and hence thumbnail can be very expensive. Since a given product may have many different advertisement layouts with the same photo, thumbnail may need to be computed many times on the same image object. It would be wasteful to actually invoke  thumbnail on each reference to an image. 
    Question:
    1 Hive support udf cache ?
    2 How hive implement udf cache?
    


r7raul1984@163.com