HELP: Mutating Tables

I'm trying to code a DELETE SET NULL trigger (note in this instance it has to be DELETE and not DELETE OR UPDATE)

Consider

CREATE TRIGGER detail_set_null AFTER DELETE ON master REFERENCING OLD AS deleted
FOR EACH ROW
BEGIN
   UPDATE detail SET
     detail.foreignkey = NULL
   WHERE detail.foreignkey = :deleted.primarykey; END If I create the trigger as AFTER DELETE, I get an RI error from Oracle telling me that dependant detail rows exist. If I create the trigger as BEFORE DELETE, I get a mutating table exception on master.

How do I get round it?

Replies by email please.

TIA.

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| A. Mackay                                    EMail eddie_at_tag.co.uk   |

| http://www.tag.co.uk/tag/                                            |

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