SQL & PL/SQL

Scenario:

     - I have 2 types:

          create or replace TYPE T_STRING_TABLE AS TABLE OF VARCHAR2(32767);

          create or replace TYPE T_STRING_TABLE_2D AS TABLE OF T_STRING_TABLE;

     - In PLSQL, I have a variable with T_STRING_TABLE_2D as the datatype and it is already populated.

               v_file_arr                       T_STRING_TABLE_2D;

Question:

     1. How can I convert this two-dimensional array into a table for me to be able to INSERT those data into a table.

          INSERT in tbl_sample(

               col1, col2, ...

          )

          SELECT v_file_arr FROM dual;

          (something like this)

P.S.

I tried to research it by myself, unfortunately, I think I lack the skill in googling this topic.

Answers as links is fine with me, I can do the reading by myself (but an example code would be greatly appreciated)

Additional Note: It is for an APEX application but unfortunately,

the csv file being uploaded have more than 50 columns,

so the available plugin excel2collections is not feasible.