Pavel Stehule wrote:
What about adding something like operator ||| in the orafce package for
concat?

no, it could be confusing and it isn't enough, because it isn't only
|| or concat problem. On Oracle empty string is equal to NULL and NULL
is equal to empty string.

example: '' is null, length('')

http://www.thunderguy.com/semicolon/2003/04/26/oracle-empty-string-null/

so we are not able emulate this behave.
Hi Pavel,

Thanks for your quick reply. What you say is entirely true, however I'm not sure if you completely understood my question, so please do not be offended if I try to elaborate it a bit:

I did not ask for full '' = NULL emulation, only for an operator to match the concat function, so that code conversion with repetetive concats are easier (string || string || string etc) which occur frequently. Ofcourse a translator can be made that converst that to concat(string,concat(string,concat(string etc))), however that's confusing too in a different way. So imho the only problem is to think of an operator that somehow resembles || so the programmer recognizes a concat, but also adds something so the programmer recognizes: not strict. What about ||+ ?

And then, at the conversion of e.g. (string || string || string) IS NULL, confusion arises, but this is not due to the concat, but more to the IS NULL clause together with the strange '' = null, and that must be handled otherwise.

So the operator would speed up part of the code conversion.

regards,
Yeb Havinga




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