What Are Named Parameters? - Oracle DBA FAQ - Creating Your Own PL/SQL Procedures and Functions

Named parameters are actual parameters specified not by position but by providing formal parameter names when calling the procedure or function. The main advantage of named parameters is that the caller don't have to remember the position of each parameter. But the caller have to remember the formal parameter names. The script below illustrates how to use named parameters:

SQL> CREATE OR REPLACE PROCEDURE SWAP_TEST AS
  2    A NUMBER := 3;
  3    B NUMBER := 8;
  4    PROCEDURE MY_SWAP(X IN OUT NUMBER,Y IN OUT NUMBER) AS
  5      T NUMBER;
  6    BEGIN
  7      T := X;
  8      X := Y;
  9      Y := T;
 10    END MY_SWAP;
 11  BEGIN
 12    MY_SWAP(Y=>B, X=>A); -- same as (X=>A, Y=B), OR (A,B)
 13    DBMS_OUTPUT.PUT_LINE('A = ' || TO_CHAR(A));
 14    DBMS_OUTPUT.PUT_LINE('B = ' || TO_CHAR(B));
 15  END;
 16  /

SQL> EXECUTE SWAP_TEST;
A = 8
B = 3