[TYPO3-dev] Re: TCA select - Insert NULL

[Elmar Hinz]

You don't mention, if the ERROR is in the FE (extbase) or in the BE (TCA forms).

>From the mere point of HTML forms a value of NULL does make fewer sense,
because HTML can only use strings as values. However, the error is 
not from HTML but from SQL.

For the issues with extbase I can't give solutions. I simply avoid it, when I don't have a rational reason to use. 

You may try "--" as a value instead of "" and "0", but It will likely result in a similar SQL Error.

You could consider a giant number as workaround, a number never reached by your entries.

No other ideas.

Regards

Elmar