How to avoid duplicate row where one column value will get first table?

I have two tables. And I want to avoid duplicate values where one column value will get from any table.
table a

table b

expected result

here

the row will be removed.

Use UNION ALL to concatenate the two tables with an additional priority column and then use the ROW_NUMBER analytic function to find each row with the highest priority:

SELECT id,
       value,
       name,
       pid
FROM   (
  SELECT id,
         value,
         name,
         pid,
         ROW_NUMBER() OVER (PARTITION BY id, value, name ORDER BY priority) AS rn
  FROM   (
    SELECT id, value, name, pid, 1 AS priority FROM a UNION ALL
    SELECT id, value, name, pid, 2 AS priority FROM b
  )
)
WHERE  rn = 1;

Which, for the sample data:

CREATE TABLE a (id, name, value, pid) AS
SELECT 1, 'a', 55, 27 FROM DUAL UNION ALL
SELECT 2, 'b', 56, 23 FROM DUAL UNION ALL
SELECT 3, 'c', 57, 22 FROM DUAL;

CREATE TABLE b (id, name, value, pid) AS
SELECT 1, 'a', 55, 29 FROM DUAL UNION ALL
SELECT 5, 'd', 58, 23 FROM DUAL UNION ALL
SELECT 6, 'e', 59, 22 FROM DUAL;

Outputs:

fiddle