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== fetch



=== Purpose


Configures the fetching behavior of an association.


=== Examples


[source,groovy]
----
class Author {

    static hasMany = [books: Book]

    static mapping = {
        books fetch: 'join'
    }
}
----


=== Description


Usage: `association_name(fetch:string)`

Arguments:

* `fetchStrategy` - The fetching strategy to use. Either `join` or `select`.

By default GORM assumes fetching of associations is done using a `SELECT` when the association is accessed. If you prefer that the association be fetched eagerly at the same time then you can override the behavior:

[source,groovy]
----
class Author {

    static hasMany = [books: Book]

    static mapping = {
        books fetch: 'join'
    }
}
----

Here the `books` association will be fetched using a join at the same time the author is retrieved, for example:

[source,groovy]
----
def author = Author.get(1)
// the books collection is pre-initialized - no risk of lazy loading exceptions
----

Note that excessive use of joins can be a performance bottleneck. See the section on  link:{hibernate5GuideFromRef}index.html#fetching[Eager vs Lazing Fetching] in the user guide.
