15.10 CREATE PACKAGE BODY Statement
The CREATE
PACKAGE
BODY
statement creates or replaces the body of a stored package, which is an encapsulated collection of related procedures, stored functions, and other program objects stored as a unit in the database.
The package body defines these objects. The package specification, defined in an earlier CREATE
PACKAGE
statement, declares these objects.
Packages are an alternative to creating procedures and functions as standalone schema objects.
Topics
Prerequisites
To create or replace a package in your schema, you must have the CREATE
PROCEDURE
system privilege. To create or replace a package in another user's schema, you must have the CREATE
ANY
PROCEDURE
system privilege. In both cases, the package body must be created in the same schema as the package.
To embed a CREATE
PACKAGE
BODY
statement inside an the database precompiler program, you must terminate the statement with the keyword END-EXEC
followed by the embedded SQL statement terminator for the specific language.
Syntax
create_package_body ::=
plsql_package_body_source ::=
initialize_section ::=
Semantics
create_package_body
OR REPLACE
Re-creates the package body if it exists, and recompiles it.
Users who were granted privileges on the package body before it was redefined can still access the package without being regranted the privileges.
[ EDITIONABLE | NONEDITIONABLE ]
If you do not specify this property, then the package body inherits EDITIONABLE
or NONEDITIONABLE
from the package specification. If you do specify this property, then it must match that of the package specification.
plsql_package_body_source
schema
Name of the schema containing the package. Default: your schema.
package_name
Name of the package to be created.
declare_section
Has a definition for every cursor and subprogram declaration in the package specification. The headings of corresponding subprogram declarations and definitions must match word for word, except for white space.
Can also declare and define private items that can be referenced only from inside the package.
Restriction on declare_section
PRAGMA
AUTONOMOUS_TRANSACTION
cannot appear here.
initialize_section
Initializes variables and does any other one-time setup steps.
Examples
Example 15-20 Creating the emp_mgmt Package Body
This statement creates the body of the emp_mgmt
package created in "Example 15-19".
CREATE OR REPLACE PACKAGE BODY emp_mgmt AS
tot_emps NUMBER;
tot_depts NUMBER;
FUNCTION hire
(last_name VARCHAR2, job_id VARCHAR2,
manager_id NUMBER, salary NUMBER,
commission_pct NUMBER, department_id NUMBER)
RETURN NUMBER IS new_empno NUMBER;
BEGIN
SELECT employees_seq.NEXTVAL
INTO new_empno
FROM DUAL;
INSERT INTO employees
VALUES (new_empno, 'First', 'Last','first.example@example.com',
'(415)555-0100',
TO_DATE('18-JUN-2002','DD-MON-YYYY'),
'IT_PROG',90000000,00, 100,110);
tot_emps := tot_emps + 1;
RETURN(new_empno);
END;
FUNCTION create_dept(department_id NUMBER, location_id NUMBER)
RETURN NUMBER IS
new_deptno NUMBER;
BEGIN
SELECT departments_seq.NEXTVAL
INTO new_deptno
FROM dual;
INSERT INTO departments
VALUES (new_deptno, 'department name', 100, 1700);
tot_depts := tot_depts + 1;
RETURN(new_deptno);
END;
PROCEDURE remove_emp (employee_id NUMBER) IS
BEGIN
DELETE FROM employees
WHERE employees.employee_id = remove_emp.employee_id;
tot_emps := tot_emps - 1;
END;
PROCEDURE remove_dept(department_id NUMBER) IS
BEGIN
DELETE FROM departments
WHERE departments.department_id = remove_dept.department_id;
tot_depts := tot_depts - 1;
SELECT COUNT(*) INTO tot_emps FROM employees;
END;
PROCEDURE increase_sal(employee_id NUMBER, salary_incr NUMBER) IS
curr_sal NUMBER;
BEGIN
SELECT salary INTO curr_sal FROM employees
WHERE employees.employee_id = increase_sal.employee_id;
IF curr_sal IS NULL
THEN RAISE no_sal;
ELSE
UPDATE employees
SET salary = salary + salary_incr
WHERE employee_id = employee_id;
END IF;
END;
PROCEDURE increase_comm(employee_id NUMBER, comm_incr NUMBER) IS
curr_comm NUMBER;
BEGIN
SELECT commission_pct
INTO curr_comm
FROM employees
WHERE employees.employee_id = increase_comm.employee_id;
IF curr_comm IS NULL
THEN RAISE no_comm;
ELSE
UPDATE employees
SET commission_pct = commission_pct + comm_incr;
END IF;
END;
END emp_mgmt;
The package body defines the public program objects declared in the package specification:
-
The functions
hire
andcreate_dept
-
The procedures
remove_emp
,remove_dept
,increase_sal
, andincrease_comm
These objects are declared in the package specification, so they can be called by application programs, procedures, and functions outside the package. For example, if you have access to the package, you can create a procedure increase_all_comms
separate from the emp_mgmt
package that invokes the increase_comm
procedure.
These objects are defined in the package body, so you can change their definitions without causing the database to invalidate dependent schema objects. For example, if you subsequently change the definition of hire
, then the database need not recompile increase_all_comms
before running it.
The package body in this example also declares private program objects, the variables tot_emps
and tot_depts
. These objects are declared in the package body rather than the package specification, so they are accessible to other objects in the package, but they are not accessible outside the package. For example, you cannot develop an application that explicitly changes the value of the variable tot_depts
. However, the function create_dept
is part of the package, so create_dept
can change the value of tot_depts
.
Related Topics
In this chapter:
In other chapters: