PL/SQL - ALTER FUNCTION

PL/SQL - ALTER FUNCTION
1. How to ALTER FUNCTION?
 Alter function is used to recompile a stand-alone stored function.
SYNTAX: ALTER FUNCTION [schema.] function COMPILE 
 
Schema 
    is the schema containing the function.  If you omit schema, Oracle 
    assumes the function is in your own schema. 
 
Function 
    is the name of the function to be recompiled. 
 
COMPILE 
Causes  Oracle to recompile the function.  The COMPILE keyword is  required. 
 
PREREQUISITES: 
 The function must be in your own schema or you must have ALTER ANY   PROCEDURE system privilege. 
 
    If you are using Trusted Oracle in DBMS MAC mode, your DBMS label  must match the function's creation label or you must satisfy one of   these criteria: 
 
* If the function's creation label is higher than your DBMS label,  you must have READUP and WRITEUP system privileges. 
 
 * If the function's creation label is lower than your DBMS label,  you must have WRITEDOWN system privilege. 
 

 * If the function's creation label and your DBMS label are   non-comparable, you must have READUP, WRITEUP, and WRITEDOWN system   privileges. 
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