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[[persistenceBasics-deletingObjects]]
== Deleting Objects

Call `delete()` on a loaded instance to remove it from the database:

[source,groovy]
----
def book = Book.get(1)
book.delete()
----

=== Flush on Delete

[source,groovy]
----
book.delete(flush: true)    // issues DELETE immediately
----

=== Cascade Delete

When a domain class declares `belongsTo`, deleting the parent also deletes its children:

[source,groovy]
----
class Author {
    static hasMany = [books: Book]
}

class Book {
    static belongsTo = [author: Author]
}

// Deletes the author AND all associated books
Author.get(1).delete()
----

To delete without cascading, remove the `belongsTo` and configure cascade behaviour explicitly — see xref:ormdsl-customCascadeBehaviour[Custom Cascade Behaviour].

=== Bulk Delete

Use `deleteAll()` to delete all instances matching a criteria:

[source,groovy]
----
Book.where { genre == 'Horror' }.deleteAll()
----

Or with HQL:

[source,groovy]
----
Book.executeUpdate("delete Book where genre = :genre", [genre: 'Horror'])
----
