Can I drop the partitioned index then recreate it?

<If one partitioned table has one partitioned index, can I drop the partitioned index then recreate it?
yes


if you have to load o lot of data, ie the full table data, it will be eventually be faster to drop the index before, and recreate if afterwards.
now, do you really load data from many/all partitions of that table?

with a partitioned table, you can simply "drop index <index_name>" to remove the index.
creating an index is also no different from a normal create index statement.  it will result in a locally partitioned index with teh partitioning aligned to the partitions of the parent table.

syntax is :
create index my_partition_idx on my_par_table ( part_column_name ) local;

This is to create a partitioned index whose partitioning will be same as that of the table.

Thanks