Make Entire Result set into a Single Row

i have to convert the entire result in Oracle into a single row result set with different column names

I have tried with some self joins but not appears to be working .

Expected output

Answer

Give each row a unique number and then PIVOT:

Oracle Setup:

CREATE TABLE table_name ( ssn, first_name, last_name ) AS
  SELECT 123456789, 'VKP', 'KKO' FROM DUAL UNION ALL
  SELECT 987654321, 'ABC', 'XYZ' FROM DUAL UNION ALL
  SELECT 332211456, 'PQR', 'GHJ' FROM DUAL

Query:

SELECT "1_SSN"        AS SSN_1,
       "1_FIRST_NAME" AS FIRST_NAME_1,
       "1_LAST_NAME"  AS LAST_NAME_1,
       "2_SSN"        AS SSN_2,
       "2_FIRST_NAME" AS FIRST_NAME_2,
       "2_LAST_NAME"  AS LAST_NAME_2,
       "3_SSN"        AS SSN_3,
       "3_FIRST_NAME" AS FIRST_NAME_3,
       "3_LAST_NAME"  AS LAST_NAME_3
FROM   (
  SELECT t.*,
         ROWNUM AS rn
  FROM   table_name t
)
PIVOT(
  MAX( SSN        ) AS SSN,
  MAX( FIRST_NAME ) AS first_name,
  MAX( LAST_NAME  ) AS last_name
  FOR rn IN (1, 2, 3)
)

Output:

    SSN_1 | FIRST_NAME_1 | LAST_NAME_1 |     SSN_2 | FIRST_NAME_2 | LAST_NAME_2 |     SSN_3 | FIRST_NAME_3 | LAST_NAME_3
--------: | :----------- | :---------- | --------: | :----------- | :---------- | --------: | :----------- | :----------
123456789 | VKP          | KKO         | 987654321 | ABC          | XYZ         | 332211456 | PQR          | GHJ        

db<>fiddle here