, or sn) only before comparing it to the first argument (e), rather than evaluating all search. It keeps the honest people honest as it provides a thin veil of protection from "curious" eyes. The DECODE() function evaluates each search value (s1, s2. The WRAP utility keeps the less motivated attackers at bay, but it isn't unbreakable (and I don't believe anyone ever said it was). Tom, How to use a like operator in decode. Anyway, decode works fine in my procedure. As far as I know, nothing prevents one from using a SQL function in a PL/SQL program. The functionality of DECODE in ORACLE with following flowchart. And it finally converts back the datatype of result to the datatype of the expression. They have to, and so they fail to provide ironclad protection. 1 DECODE is a SQL function, not a PL/SQL function. The DECODE function automatically converts or casts the expression to the data type of the first search argument or search1. Just like most DRM schemes, the attacker possesses, in some form, the key and/or algorithm to decrypt the message. In Oracle, you can use DECODE function to evaluate a list of expressions, and if a value is matched return the corresponding result. These are mutually exclusive, and yet you expect both. Where is Carol? You are essentially making Bob and Carol the same person! You WANT Bob to be able to decrypt Alice's message (which is necessary to execute the code), but you do NOT WANT him to be able to decrypt the message (as there are trade secrets or whatever). In this case, Alice wrote the code, and Bob wants to run that code. DECODE and CASE statements in Oracle both provide a conditional construct, of this form: if A n1 then A1 else if A n2 then A2 else X Everything DECODE can. It works similar to an IF statement within other languages. It allows you to provide a value, and then evaluate other values against it and show different results. It’s similar to a CASE statement, but CASE is a statement where DECODE is a function. This won't work for encrypting code that you want a user to be able to execute. The purpose of the Oracle DECODE function is to perform an IF-THEN-ELSE function. Alice has a Bob's public key, Bob keeps his private key, and Carol can't figure out what the message is without the private key (even with Bob's public key). Strong encryptions with public/private keys work well here. In traditional encryption, you have Alice wanting to send a message (an email for example) to Bob without Carol being able to see the message. You are encrypting a message with the intent of having it decrypted. It is NOT a one-way hash, as you expect that the user who receives the wrapped package will be able to execute the package as originally written. When you wrap a package, what is really happening? It is encryption of plain-text using some algorithm. I get the feeling that people who ask about unwrapping wrapped code or having public key encryption applied to code don't fully grasp the security concepts involved.
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