How to modify a stored procedure?

Question

How can I safely change the procedure:
   PROCEDURE check_background_event ( TableName    VARCHAR2 ,
                                       StatusVal    VARCHAR2 ,
                                       KeyVal       NUMBER   ,
                                       EventString  VARCHAR2 ) IS
        StartPos   NUMBER ;
        EndPos     NUMBER ;
        Param      VARCHAR2 ( 255 ) ;
    BEGIN
        StartPos := INSTR ( EventString , '(' || StatusVal ) ;
        EndPos   := INSTR ( EventString , ')' , StartPos ) ;
        IF StartPos > 0 AND EndPos > StartPos THEN
            Param := SUBSTR ( EventString , StartPos + 3 , EndPos - StartPos - 3 ) ;
            -- Check if this event should be logged
            record_notes ( TableName , StatusVal , KeyVal , Param ) ;
            INSERT INTO background
               ( background_id , priority , session_id ,
                 background_task_type_id , parameter , active )
              SELECT
                 sq_background . nextval , 1 , lims_env . session_id ,
                 background_task_type_id , TableName || ',' || TO_CHAR ( KeyVal ) || ',' || Param , 'F'
                FROM background_task_type
                WHERE name = 'Event' ;
        END IF ;
    END check_background_event ;into:
   PROCEDURE check_background_event ( TableName    VARCHAR2 ,
                                       StatusVal    VARCHAR2 ,
                                       KeyVal       NUMBER   ,
                                       EventString  VARCHAR2 ) IS
        StartPos   NUMBER ;
        EndPos     NUMBER ;
        Param      VARCHAR2 ( 255 ) ;
     u_Prio       NUMBER ;
    BEGIN
        StartPos := INSTR ( EventString , '(' || StatusVal ) ;
        EndPos   := INSTR ( EventString , ')' , StartPos ) ;
        IF StartPos > 0 AND EndPos > StartPos THEN
            Param := SUBSTR ( EventString , StartPos + 3 , EndPos - StartPos - 3 ) ;
            -- Check if this event should be logged
            record_notes ( TableName , StatusVal , KeyVal , Param ) ;
            IF INSTR(TableName ,'P') = 1 THEN
               u_Prio := 1 ;
            ELSE
               u_Prio := 3 ;
            END IF ;
            INSERT INTO background
               ( background_id , priority , session_id ,
                 background_task_type_id , parameter , active )
              SELECT
                 sq_background . nextval , u_Prio , lims_env . session_id ,
                 background_task_type_id , TableName || ',' || TO_CHAR ( KeyVal ) || ',' || Param , 'F'
                FROM background_task_type
                WHERE name = 'Event' ;
        END IF ;
    END check_background_event ;

Answer 1

It is also a procedure.
CREATE OR REPLACE PACKAGE lims_status AS
    PROCEDURE check_study_status         ( KeyValue NUMBER , StatusValue VARCHAR2 ) ;
    PROCEDURE check_sdg_status           ( KeyValue NUMBER , StatusValue VARCHAR2 ) ;
    PROCEDURE check_sample_status        ( KeyValue NUMBER , StatusValue VARCHAR2 ) ;
    PROCEDURE check_parentaliquot_status ( KeyValue NUMBER , StatusValue VARCHAR2 , IgnoreFlag BOOLEAN DEFAULT FALSE ) ;
    PROCEDURE check_aliquot_status       ( KeyValue NUMBER , StatusValue VARCHAR2 ) ;
    PROCEDURE check_test_status          ( KeyValue NUMBER , StatusValue VARCHAR2 ) ;
    PROCEDURE check_parentplate_status   ( KeyValue NUMBER , StatusValue VARCHAR2 , IgnoreFlag BOOLEAN DEFAULT FALSE ) ;
    PROCEDURE check_plate_status         ( KeyValue NUMBER , StatusValue VARCHAR2 ) ;
    PROCEDURE check_plate_plan_status    ( KeyValue NUMBER , StatusValue VARCHAR2 ) ;
    PROCEDURE reset_current_transaction ;
    PROCEDURE propagate_study_status ;
    PROCEDURE propagate_sdg_status ;
    PROCEDURE propagate_sample_status ;
    PROCEDURE propagate_aliquot_status ;
    PROCEDURE propagate_parentaliquot_status ;
    PROCEDURE propagate_test_status ;
    PROCEDURE propagate_parentplate_status ;
    PROCEDURE propagate_plate_status ;
    PROCEDURE propagate_plate_plan_status ; 
    -- Procedures call from workflows to continue authorisation propagation
    PROCEDURE force_propagate_sample  ( KeyValue NUMBER ) ;
    PROCEDURE force_propagate_aliquot ( KeyValue NUMBER ) ;
    PROCEDURE force_propagate_test    ( KeyValue NUMBER ) ;
    PROCEDURE force_propagate_result  ( KeyValue NUMBER ) ;
    PROCEDURE force_propagate_plate   ( KeyValue NUMBER ) ;   
    -- Add events to the background queue
    PROCEDURE check_background_event ( TableName VARCHAR2 , StatusVal VARCHAR2 , KeyVal NUMBER , EventString VARCHAR2 ) ;
    -- Record notes for an entity
    PROCEDURE record_notes ( TableName VARCHAR2 , StatusVal VARCHAR2 , KeyVal NUMBER , EventString VARCHAR2 ) ;
    FUNCTION update_old_status ( OldStatus VARCHAR2 , NewStatus CHAR , CurrentStatus CHAR ) RETURN VARCHAR2 ;
-- Status changing procedures
    PROCEDURE unapprove_sample     ( SampleId  NUMBER ) ;
    PROCEDURE unapprove_plate      ( PlateId   NUMBER ) ;
    PROCEDURE unapprove_plate_plan ( PlatePlanId NUMBER) ;
  PROCEDURE complete_study       ( StudyId   NUMBER ) ;
  PROCEDURE complete_sdg         ( SdgId     NUMBER ) ;
PROCEDURE complete_sample      ( SampleId  NUMBER ) ;
PROCEDURE complete_aliquot     ( AliquotId NUMBER ) ;
PROCEDURE complete_test        ( TestId    NUMBER ) ;
PROCEDURE complete_plate       ( PlateId   NUMBER ) ;
PROCEDURE complete_plate_plan  ( PlatePlanId NUMBER ) ;
-- Update the replicate count on tests
PROCEDURE check_test_replicates      ( AliquotId NUMBER ) ;
PROCEDURE check_platetest_replicates ( PlateId NUMBER ) ;
    PROCEDURE check_transaction ;
    -- Procedure and Function to control Aliquot Authorisation
    PROCEDURE add_aliquot_propagation ( KeyValue NUMBER ) ;
    FUNCTION aliquot_propagated ( KeyValue NUMBER ) RETURN BOOLEAN ;
    -- Procedures and Functions to control Number of Recursive Calls
    PROCEDURE start_post_aliquot_call ;
    PROCEDURE start_post_plate_call   ;
    PROCEDURE end_post_aliquot_call   ;
    PROCEDURE end_post_plate_call     ;
    FUNCTION needs_stop_post_aliquot RETURN BOOLEAN ;
    FUNCTION needs_stop_post_plate   RETURN BOOLEAN ;
    study_propagating           BOOLEAN := FALSE ;
    sdg_propagating             BOOLEAN := FALSE ;
    sample_propagating          BOOLEAN := FALSE ;
    parentaliquot_propagating   BOOLEAN := FALSE ;
    aliquot_propagating         BOOLEAN := FALSE ;
    test_propagating            BOOLEAN := FALSE ;
    parentplate_propagating     BOOLEAN := FALSE ;
    plate_propagating           BOOLEAN := FALSE ;
    plate_plan_propagating      BOOLEAN := FALSE ;
    -- Variables to control Number of Recursive Call
    stop_aliquot_propagating    BOOLEAN := FALSE ;
    stop_plate_propagating      BOOLEAN := FALSE ;
    -- Variables to control Complete status propagation
    study_from_propagate      NUMBER := 0 ;
    sdg_from_propagate        NUMBER := 0 ;
    sample_from_propagate     NUMBER := 0 ;
    aliquot_from_propagate    NUMBER := 0 ;
    plate_from_propagate      NUMBER := 0 ;
    plate_plan_from_propagate NUMBER := 0 ;
END lims_status ;