db-derby-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Spezifikum <i...@spezifikum.com>
Subject Re: SQL Problem with foreign key (statement rolled back)
Date Mon, 31 Oct 2011 18:58:43 GMT
Am 31.10.2011 09:43, schrieb Knut Anders Hatlen:
> Spezifikum<info@spezifikum.com>  writes:
>
>> Hi,
>> i get the error message
>> "SQLIntegrityConstraintViolationException: UPDATE on table 'CDENTRY'
>> caused a violation of foreign key constraint 'LINKEDTO_FK' for key
>> (0).  The statement has been rolled back."
>> I see, why Derby refuses to do so and i am indeed thankfull that it
>> does handle this, but i don't know how to get around it.
>> The relevent part of my table is:
>> Table name: CDEntry
>> ID=INT NOT NULL GENERATED ALWAYS AS IDENTITY(START WITH 1, INCREMENT
>> BY 1) PRIMARY KEY
>> linkedTo=INT CONSTRAINT linkedTo_FK REFERENCES CDEntry
>>
>> One CDEntry line may be linked to exactly one other and quite often will be.
>> Sometimes that link has to be deleted, so i try:
>> "UPDATE CDEntry set linkedTo=0 where linkedTo=?"
>> "UPDATE CDEntry set linkedTo=0 where ID=?"
>> Executing these in any order gives me the errormessage above.
>> How do i solve that?
> Does it work if you set linkedTo to NULL instead of 0?
>
Ähm, I should have known that, right? Anyway, yes, thanks a lot, it works!

Mime
View raw message