DevOps, CI/CD and Automation

This is My Table i want to take Sum ONly Previous Balance.... No Need to take sum all the feilds

SQL> desc cash;

Name Null? Type

----------------------------------------- -------- ----------------------------

C_DATE DATE

FLAG VARCHAR2(10)

DESCRIPTION VARCHAR2(25)

PNAME VARCHAR2(25)

DEBIT NUMBER(8)

CREDIT NUMBER(8)

SR_NO NUMBER

VEH_NO VARCHAR2(25)

This is Report Query

SELECT SR_NO, C_DATE, VEH_NO, DESCRIPTION, DEBIT, CREDIT

FROM ( SELECT NULL SR_NO, NULL C_DATE, NULL VEH_NO, 'Previus Balance' DESCRIPTION,

        CASE WHEN BAL > 0 THEN BAL

             ELSE NULL END DEBIT,

        CASE WHEN BAL \< 0 THEN BAL

             ELSE NULL END CREDIT

   FROM (SELECT SUM(NVL(DEBIT, 0) - NVL(CREDIT, 0)) BAL

         FROM CASH

         WHERE PNAME= :P\_NAME  AND  C\_DATE \<:P\_FROM\_DATE)

         UNION ALL

         SELECT SR\_NO, C\_DATE, VEH\_NO, DESCRIPTION, DEBIT, CREDIT

         FROM CASH

         WHERE PNAME= :P\_NAME  AND  C\_DATE BETWEEN :P\_FROM\_DATE  AND  :P\_TO\_DATE)

ORDER BY SR_NO NULLS FIRST;