Column Values Comparison

Question

I have a table product with two columns product id & product name with below data
Product ID Product Name
P1 X
P1 Y
P1
P2 X
P2 X
P2 X
P3 NULL
P3 NULL
I need to add a new row in same table with one row containg product id & product name with below conditions
1) If there are different values in column product name across product id then i need to insert a new row with value null across column product name for that product id.
2) if there are same values in product name column across product id then I need to insert a new row with value in column product name for that productid.
3) if there are null values in column product name across product id then I need to insert a new row with null value in product name column across product id.
Below is the result how it should be with new row.
Product ID Product Name
P1 X
P1 Y
P1
P1 NULL -- New row
P2 X
P2 X
P2 X
P2 NULL -- New row
P3 NULL
P3 NULL
P3 NULL -- New row
If any one knows on how to handle by writing a procedure please help with a procedure. help will be highly appreciated.
Thanks in advance :)

Answer 1

Maybe this will help
Select * from STATE_MAS ;
STATE
A
B
D
F
H
Select * from STATE_CHILD
  STATE_A   STATE_B   STATE_C   STATE_D   STATE_E   STATE_F   STATE_G   STATE_H   STATE_I   STATE_J
        1         0         0         1         1         0         0         0         0         0
CREATE OR REPLACE FUNCTION GET_STATE (P_VAL VARCHAR) RETURN NUMBER IS
V_SQL VARCHAR2(200);
V_COL VARCHAR2(35);
P_RETURN NUMBER ;
BEGIN
V_COL := 'STATE_'||P_VAL;
V_SQL := 'SELECT 1 FROM STATE_CHILD WHERE '||V_COL||' = 1 ';
EXECUTE IMMEDIATE  V_SQL INTO P_RETURN ;
RETURN P_RETURN ;
END;
SELECT STATE FROM STATE_MAS
WHERE GET_STATE(STATE) = 1 ;
STATE
A
D