ALTER PACKAGE

Purpose

Use the ALTER PACKAGE statement to explicitly recompile a package specification, body, or both. Explicit recompilation eliminates the need for implicit run-time recompilation and prevents associated run-time compilation errors and performance overhead.

Because all objects in a package are stored as a unit, the ALTER PACKAGE statement recompiles all package objects together. You cannot use the ALTER PROCEDURE statement or ALTER FUNCTION statement to recompile individually a procedure or function that is part of a package.

Prerequisites

For you to modify a package, the package must be in your own schema or you must have ALTER ANY PROCEDURE system privilege.

Syntax

alter_package::=

Text description of alter_package

Semantics

schema

Specify the schema containing the package. If you omit schema, Oracle assumes the package is in your own schema.

package

Specify the name of the package to be recompiled.

COMPILE

You must specify COMPILE to recompile the package specification or body. The COMPILE keyword is required.

During recompilation, Oracle drops all persistent compiler switch settings, retrieves them again from the session, and stores them at the end of compilation. To avoid this process, specify the REUSE SETTINGS clause.

If recompiling the package results in compilation errors, Oracle returns an error and the body remains invalid. You can see the associated compiler error messages with the SQL*Plus command SHOW ERRORS.

SPECIFICATION

Specify SPECIFICATION to recompile only the package specification, regardless of whether it is invalid. You might want to recompile a package specification to check for compilation errors after modifying the specification.

When you recompile a package specification, Oracle invalidates any local objects that depend on the specification, such as procedures that call procedures or functions in the package. The body of a package also depends on its specification. If you subsequently reference one of these dependent objects without first explicitly recompiling it, Oracle recompiles it implicitly at run time.

BODY

Specify BODY to recompile only the package body regardless of whether it is invalid. You might want to recompile a package body after modifying it. Recompiling a package body does not invalidate objects that depend upon the package specification.

When you recompile a package body, Oracle first recompiles the objects on which the body depends, if any of those objects are invalid. If Oracle recompiles the body successfully, the body becomes valid.

PACKAGE

Specify PACKAGE to recompile both the package specification and the package body if one exists, regardless of whether they are invalid. This is the default. The recompilation of the package specification and body lead to the invalidation and recompilation as described for SPECIFICATION and BODY.

DEBUG

Specify DEBUG to instruct the PL/SQL compiler to generate and store the code for use by the PL/SQL debugger.

REUSE SETTINGS

Specify REUSE SETTINGS to prevent Oracle from dropping and reacquiring compiler switch settings. With this clause, Oracle preserves the existing settings and uses them for the recompilation.

If you specify both DEBUG and REUSE SETTINGS, Oracle sets the persistently stored value of the PLSQL_COMPILER_FLAGS parameter to INTERPRETED, DEBUG. No other compiler switch values are changed.

Examples

Recompiling a Package: Examples

This statement explicitly recompiles the specification and body of the hr.emp_mgmt package that was created in "Creating a Package: Example":

ALTER PACKAGE emp_mgmt
   COMPILE PACKAGE; 

If Oracle encounters no compilation errors while recompiling the accounting specification and body, emp_mgmt becomes valid. The user hr can subsequently call or reference all package objects declared in the specification of emp_mgmt without run-time recompilation. If recompiling emp_mgmt results in compilation errors, Oracle returns an error and emp_mgmt remains invalid.

Oracle also invalidates all objects that depend upon emp_mgmt. If you subsequently reference one of these objects without explicitly recompiling it first, Oracle recompiles it implicitly at run time.

To recompile the body of the emp_mgmt package in the schema hr, issue the following statement:

ALTER PACKAGE hr.emp_mgmt 
   COMPILE BODY; 

If Oracle encounters no compilation errors while recompiling the package body, the body becomes valid. The user hr can subsequently call or reference all package objects declared in the specification of emp_mgmt without run-time recompilation. If recompiling the body results in compilation errors, Oracle returns an error message and the body remains invalid.

Because this statement recompiles the body and not the specification of emp_mgmt, Oracle does not invalidate dependent objects.