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Can you give examples of an atomic value and a non atomic value in the context of relational database?

Chris Martin
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Aboria
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  • http://www.postgresql.org/docs/7.1/static/non-atomic-values.html – Sam Dec 11 '13 at 23:46
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    What "atomic" means depends on how you intend to search for, read and write the data. Theoretically, a same value can be atomic or non-atomic depending on your requirements. Here is [one example](http://stackoverflow.com/a/20316650/533120). – Branko Dimitrijevic Dec 12 '13 at 02:19

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The concept of atomicity is extremely hard to pin down precisely.

So much so that the concept itself has been pretty much totally abandoned in modern relational database theory.

Google for "What first normal form really means", and related material.

Also you might spend some time pondering the following two cases :

A set, is that a "further divisible" thing, typically because there are "obviously" members in the set that you "can take out of the set and put them back in" or some such ? Well, no, it isn't ! If you take a member out of a set it is no longer the same set.

An integer number, is that a "further decomposable" thing ? Well yes it is ! It can be "decomposed" in the distinct powers of two of which it is the sum !

The concept of atomicity has no real absolute meaning in database theory.

Erwin Smout
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