Can someone help in simplifying below query. Cost of it shows as 58.

b.dueDate and b.tID are composite key.
a.tID is primary key and foreign key between table 1 and 2.

```
SELECT test.tID, test.sor_acct_id, test.pmt, test.status FROM   ct.tab1 a, 
   (SELECT a.tID, a.sor_acct_id, b.dueDate, b.amt, b.status, a.pmt, 
           Row_number() OVER ( partition BY a.tID ORDER BY b.dueDate DESC) AS rn 
    FROM   ct.tab1 a 
           INNER JOIN ct.tab2 b 
                   ON a.tID = b.tID 
    WHERE  a.tID IN (SELECT a.tID 
                              FROM   ct.tab1 a 
                                     INNER JOIN 
                                     ct.tab2 b 
                                             ON a.tID = 
                                                b.tID 
                              WHERE  a.status = 'E' 
                                     AND a.pmt IS NOT NULL 
                                     AND a.pmt <> '{}' 
                                     AND b.dueDate > CURRENT_DATE - 4 
                                     AND b.dueDate < CURRENT_DATE) 
           AND b.dueDate > CURRENT_DATE - 1 
   ) test WHERE  rn = 1 
   AND test.status IN ( 'X', 'Z' ) 
   AND a.tID = test.tID

```