Convert a 200Million heap table into table with composite partition - using Exchange Subpartition

 Hey Guys, I have a heap table with 200+ Million rows. I know this should have been created as a partitioned table but wasn't for some strange reasons! I now need to create partitioned table and looking to do the following:

Existing table structure is

CREATE TABLE Sales_data (

  id            NUMBER(10),

  item_id number,

  location_id number,

  sales_date date,

  created_date  DATE,

...

...

)

The primary key is the combination of id, item_id, location_id and sales date.

I now create a replica of the source table with the same constraints and indexes (local)

CREATE TABLE sales_part (

  id            NUMBER(10),

  item_id number,