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sql server - Self-referencing constraint in MS SQL

Is it true that MS SQL restrict self-referencing constraints with ON DELETE CASCADE option? I have a table with parent-child relation, PARENT_ID column is foreign key for ID. Creating it with ON DELETE CASCADE option causes error

"Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints."

I can't believe that I have to delete this hierarchy in recursive mode. Is there any issue except triggers?

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It is the case that you cannot set up ON DELETE CASCADE on a table with self-referencing constraints. There is a potential of cyclical logic problems, hence it won't allow it.

There's a good article here - though it's for version 8 rather than 9 of SQL - though the same rules apply.


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