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Question and Answer

Connor McDonald

Thanks for the question, GK.

Asked: November 08, 2019 - 9:36 am UTC

Answered by: Connor McDonald - Last updated: November 12, 2019 - 11:06 pm UTC

Category: Database Development - Version: 11g

Viewed 1000+ times

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You Asked

Hi Tom,

Kindly suggest some one way encryption for the data in table,where no one can decrypt it?

Read few articles about this and not satisfied.

Kindly help.

and we said...

Sorry, I'm not following.

There is no such thing as "one way encryption". The definition of "encryption" is such that you *can* decrypt.

You might be referring to hashing? ie, the same input always maps to the same (garbled) output, and is non-reversible?

If that is the case, then check out either of:


which contain routines to do hashes such as MD5, SHA-1, SHA-2 (SHA-256, SHA-384, SHA-512), MD4

There are examples of both on the AskTOM site just by searching

and you rated our response

  (1 rating)


one way encryption

November 11, 2019 - 1:15 pm UTC

Reviewer: Laurent Schneider from Switzerland

I would recommend reading

If I have an input 123 and I encrypt this to ABC, no one can decrypt but me because I know how (I have the algorithm in my head). On the other hand if you have 123 and you produce hXz and noone can decrypt it, it is pretty useless.

Usually in encryption you have a key and an algorithm.

For instance, in its simplest form , XOR

I have value 5 and key 9
0x0101 (5)
0x1001 (9)
0x1101 (13)
5 XOR 9 = 13

and noone, without the key, can decrypt it

but with the key 13 XOR 9 = 5
0x1101 (13)
0x1001 (9)
0x0101 (5)

you should well protect your key (e.g. in a wallet), so nobody can access it.

While the algorythm evolves in the last 15 years, I still recommend Arup example :


Connor McDonald


November 12, 2019 - 11:06 pm UTC

nice input

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