> But if we could find a way to represent that it would make a lot of common use
> cases much more convenient to use.
>
>>> (But that sounds rather like pie in the sky, actually. Which other
>>> databases can do that, and how do they do it?)
>> Oracle does it, by building a big index. Few people use it.
>
> The people that use it are the people stuck by dogmatic rules about "every
> table must have a primary key" or "every logical constraint must be protected
> by a database constraint". Ie, database shops run by the CYA principle.
Or ones that actually believe that every table where possible should
have a primary key.
There are very, very few instances in good design where a table does not
have a primary key.
It has nothing to do with CYA.
Joshua D. Drake
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