Outputting num_array Procedure Results in Oracle PL/SQL: A Comprehensive Guide

Understanding PL/SQL Procedures and Outputting Results with Num_Array Data Type

As a developer working with Oracle databases, you have likely encountered the num_array data type in PL/SQL. This data type represents an array of numbers, which can be useful for storing and manipulating large amounts of numerical data. In this article, we will explore how to output the results of a procedure that returns a num_array data type.

The num_array Data Type

Before diving into the specifics of outputting num_array procedure results, let’s take a brief look at what the num_array data type is and how it differs from other numeric data types in Oracle.

In PL/SQL, num_array is a user-defined data type that represents an array of numbers. It is declared using the NUM_ARRAY keyword and can be used to store and manipulate large amounts of numerical data. The num_array data type has several key features:

Fixed or Variable Length: The length of the array can be specified at declaration time, allowing for both fixed-length arrays and variable-length arrays.
Nullability: Elements in an array can be null, which means they do not contain a valid value.

Declaring and Using Procedures with num_array

To output the results of a procedure that returns a num_array data type, you first need to declare a variable or cursor to hold the returned values. Here’s a brief overview of how to declare and use procedures with num_array.

Example Procedure Declaration

PROCEDURE GET_STATUS_LIST (P_MODUL_ID      IN     NUMBER,
                            P_DOCUMENT_ID   IN     NUMBER,
                            P_USER_ID       IN     NUMBER,
                            P_STATUS_LIST   OUT NUM_ARRAY);

In the example above, we have declared a procedure named GET_STATUS_LIST that takes four parameters: P_MODUL_ID, P_DOCUMENT_ID, P_USER_ID, and P_STATUS_LIST. The P_STATUS_LIST parameter is an output parameter of type NUM_ARRAY.

Example Procedure Call

DECLARE
    alma    num_array;
BEGIN
    schema.pk_common_confirmation.get_status_list (816,
                                                     17025214,
                                                     263,
                                                     alma);
END;

In the example above, we declare a variable named alma of type num_array. We then call the get_status_list procedure and pass in the required parameters. The returned values are stored in the alma variable.

Outputting num_array Procedure Results

Now that we have declared and used procedures with num_array, let’s explore different ways to output the results of a procedure that returns this data type.

Using DBMS_OUTPUT

DECLARE
    alma    num_array;
BEGIN
    schema.pk_common_confirmation.get_status_list (816,
                                                     17025214,
                                                     263,
                                                     alma);

    FOR i IN 1..alma.count LOOP
        DBMS_OUTPUT.put_line(alma(i));
    END LOOP;
END;

In the example above, we use a FOR loop to iterate over the elements of the alma array and output each value using DBMS_OUTPUT.put_line.

Using SELECT or RETURN SYS_REFCURSOR

DECLARE
    alma    num_array;
    armud   SYS_REFCURSOR;
BEGIN
    schema.pk_common_confirmation.get_status_list (816,
                                                     17025214,
                                                     263,
                                                     alma);

    OPEN armud FOR SELECT * FROM TABLE(alma);
    FETCH armud INTO t;

    WHILE armud%NOTFOUND LOOP
        DBMS_OUTPUT.put_line(t);
        FETCH armud INTO t;
    END LOOP;

    CLOSE armud;
END;

DECLARE
    alma    num_array;
BEGIN
    SELECT schema.pk_common_confirmation.get_status_list (816,
                                                          17025214,
                                                          263,
                                                          alma)
      FROM DUAL;

    FOR i IN 1..alma.count LOOP
        DBMS_OUTPUT.put_line(alma(i));
    END LOOP;
END;

DECLARE
    alma    num_array;
BEGIN
    schema.pk_common_confirmation.get_status_list (816,
                                                     17025214,
                                                     263,
                                                     alma);

    FOR t IN (SELECT * FROM TABLE(alma))
    LOOP
        DBMS_OUTPUT.put_line(t);
    END LOOP;
END;

Using INDEX Access

DECLARE
    alma    num_array;
BEGIN
    schema.pk_common_confirmation.get_status_list (816,
                                                     17025214,
                                                     263,
                                                     alma);

    FOR i IN 1..alma.count LOOP
        DBMS_OUTPUT.put_line(alma(i));
    END LOOP;
END;

Conclusion

Outputting the results of a procedure that returns a num_array data type can be achieved through several methods, including using DBMS_OUTPUT, SELECT or RETURN SYS_REFCURSOR, and indexing access. Each method has its own advantages and disadvantages, and the choice of method depends on your specific use case.

In this article, we have explored how to output the results of a procedure that returns a num_array data type in Oracle PL/SQL. We have discussed different methods for achieving this task, including using DBMS_OUTPUT, SELECT or RETURN SYS_REFCURSOR, and indexing access.

Recommendations

When working with large datasets, it’s often beneficial to use the most efficient method possible. Here are some recommendations for outputting num_array procedure results:

Use DBMS_OUTPUT when you need to output a small number of values.
Use SELECT or RETURN SYS_REFCURSOR when you need to output a large number of values.

By following these recommendations and using the most efficient method possible, you can improve the performance and efficiency of your PL/SQL code.

Last modified on 2023-07-17