Re: [eclipselink-users] ManyToOne support for ON DELETE SET NULL?

[James Sutherland <jamesssss@xxxxxxxxx>]

You can set this on your database table constraint if you wish, EclipseLink's
schema creation does not support "ON DELETE" constraints, so you would need
to define the table constraint yourself.

In general, you should avoid doing this.  You should be reading the objects
that reference the Attribute before deletion and set their attributes to
null.  This will ensure your object model is in synch with your data model.

You could also not define the relationship to the Attribute, and instead
query for it.


jandam wrote:
> 
> ManyToOne support for ON DELETE SET NULL
> 
> Does EclipseLink (1.1.2) support "ON DELETE SET NULL"
> 
>     @JoinColumn(name = "ATTR_ID", referencedColumnName = "ID_ATTR")
>     @ManyToOne(cascade = { CascadeType.PERSIST, CascadeType.MERGE,
> CascadeType.REFRESH })
>     private Attribute    attribute;
> 
> I need to delete entity "Attribute". Does EclipseLink support setting
> "attribute" to null?
> 
>   Thank you for reply.
> 
>   Martin
> 
> 


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