class LegacyCdDomain {
String title
Thumbnail thumbnail
static mapping = {
thumbnail ignoreNotFound: true
}
}ignoreNotFound
Purpose
Specifies how foreign keys that reference missing rows are handled in many-to-one relationships.
Examples
class Thumbnail {
byte[] data
}Description
Usage: association_name(ignoreNotFound: boolean)
When the data in the database is corrupt and a foreign key references a non existent record, Hibernate will complain with a "No row with the given identifier exists" message. For example, a LegacyCdDomain record may have a reference to a Thumbnail record with an ID of 1234, but the database may no longer contain a Thumbnail with that ID.
One possible way to load such corrupt data is to use the ignoreNotFound mapping option. If you set it to true, Hibernate will treat a missing row as a null association. So in the above example, our LegacyCdDomain instance would load but its thumbnail property would be null. Specifying a value of false for ignoreNotFound will result in Hibernate throwing an org.hibernate.ObjectNotFoundException.
A dataset loaded with ignoreNotFound: true may throw an exception during save() because of the missing reference!
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The default value for this setting is false. It maps to Hibernate’s not-found property.
This settings can be useful if you have a legacy database with unusual behaviour when it comes to referential integrity.