Greetings All,

I'm frustrated and do not understand why I cannot add a FK.

Connecting to my database (Fresh) and I'm the only person logged into Firebird 1.5. I'm using DBWorkbench where I'm trying to add a FK as follows:

ALTER TABLE AM_HISTORY_DETAIL ADD CONSTRAINT FK_AM_HISTORY_DETAIL_AM_HISTORY
FOREIGN KEY (HISTORY_ID) REFERENCES AM_HISTORY(HISTORY_ID)
ON DELETE CASCADE
ON UPDATE NO ACTION;

When I try to commit, I receive the following error:

ISC ERROR CODE 335544345

ISC ERROR MESSAGE
lock conflict on no wait transaction
unsuccessful metadata update
object AM_HISTORY is in use

How can AM_HISTORY be in use?

Any ideas what I can try?

Thanks,
Mike

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