I am working with room persistence library in android, i would appreciate if someone can help me in using foreign key, how to get data by using foreign key.
Just to summarize the above posts for future readers:
The foreign key syntax in Kotlin is
@Entity(foreignKeys = arrayOf(ForeignKey(entity = ParentClass::class,
parentColumns = arrayOf("parentClassColumn"),
childColumns = arrayOf("childClassColumn"),
onDelete = ForeignKey.CASCADE)))
The foreign key syntax in Java is:
@Entity(foreignKeys = {@ForeignKey(entity = ParentClass.class,
parentColumns = "parentClassColumn",
childColumns = "childClassColumn",
onDelete = ForeignKey.CASCADE)
})
Note: foreignKeys is an array, so in Java enclose @ForeignKey elements in { and }
You can refer to the official documentation for more information. https://developer.android.com/reference/androidx/room/ForeignKey