SQL & PL/SQL

Hello All,

What are the differences between DEFINITION and DECLARATION in plscope?

In order to get all package body procedures and functions excluding sub procedures and functions, wil the following query works?

SELECT * FROM (
    SELECT NAME, TYPE, LINE START_LINE, LEAD(LINE) OVER(ORDER BY LINE)-1 END_LINE 
    FROM (
        SELECT a.*, level lv, lpad(' ', 4 * level)||NAME FROM ( 
            SELECT *
            FROM ALL_IDENTIFIERS
            WHERE OBJECT_TYPE = 'PACKAGE BODY'
            AND OBJECT_NAME = 'PACKAGE_NAME'
            AND OWNER = USER
            AND (TYPE IN ('FUNCTION', 'PROCEDURE') OR USAGE_ID = 1)
            AND USAGE IN ('DEFINITION', 'DECLARATION')
        ) a
        START WITH USAGE_ID = 1
        CONNECT BY 
        PRIOR USAGE_ID = USAGE_CONTEXT_ID
        ORDER BY USAGE_ID
    )
    WHERE LV = 2
)

Thanks