How to do the following in Oracle?

I have this:

DROP TABLE TempTbl;        



CREATE GLOBAL TEMPORARY TABLE TempTbl (
  UPC_CD  NUMBER
) ON COMMIT DELETE ROWS;

store string to array named arrVal
arrVal () = Split(1234,344,334434,33444,",")

For i =0 to Ubound(arrVal ())

INSERT INTO  TempTbl(UPC_CD) VALUES(arrVal (i));

Next i

SELECT * FROM TempTbl;


I want to store a string of numbers into an array and then loop through the array and append the numbers to the temporary table. I want to detect if the temporary table exists, if not then create, else drop and then create.

How can this be done?