I’m trying to setup a notification service in Android Mobile using the Room API.

How do I automatically delete all notification records associated with a template_id_fk where template_id_fk can be of any 3 data classes (Income, Expense or Bill)?.

Here is the @Entity I’m trying to build for my Notification model, since Room doesn’t support Polymorphic Association out of the box, how do I setup my database to allow for this?

@Entity(
    tableName="notification",
    foreignKeys = [
        ForeignKey(
            entity = Income::class,
            parentColumns = arrayOf("uid"),
            childColumns = arrayOf("template_id_fk"),
            onDelete = ForeignKey.CASCADE,
            onUpdate = ForeignKey.CASCADE
        ),
        ForeignKey(
            entity = Expense::class,
            parentColumns = arrayOf("uid"),
            childColumns = arrayOf("template_id_fk"),
            onDelete = ForeignKey.CASCADE,
            onUpdate = ForeignKey.CASCADE
        ),
        ForeignKey(
            entity = Bill::class,
            parentColumns = arrayOf("uid"),
            childColumns = arrayOf("template_id_fk"),
            onDelete = ForeignKey.CASCADE,
            onUpdate = ForeignKey.CASCADE
        )
    ]
)
data class Notification (
    @PrimaryKey
    val uid: String = "${UUID.randomUUID()}",
    @ColumnInfo(name= "event_key")val eventKey: NotificationEventKey,
    @ColumnInfo(name= "transaction_id") val transactionId: TransactionId?,
    @ColumnInfo(name= "template_id_fk") val templateId: TemplateId,
    @ColumnInfo(name= "is_read")val isRead: Boolean = false,
    @ColumnInfo(name= "created") val created : ISODateTime,
    @ColumnInfo(name= "updated") val updated : ISODateTime,
)