Foreign key constraints in Android using SQLite? on Delete cascade

Question

I have two tables: tracks and waypoints, a track can have many waypoints, but a waypoint is assigned to only 1 track.

In the way points table I have a column called "trackidfk" which inserts the track_ID once a track is made, however I have not setup Foreign Key constraints on this column.

When I delete a track I want to delete the assigned waypoints, is this possible?. I read about using Triggers but I don't think they are supported in Android.

To create the waypoints table:

public void onCreate(SQLiteDatabase db) {     db.execSQL( "CREATE TABLE " + TABLE_NAME                  + " ("                  + _ID         + " INTEGER PRIMARY KEY AUTOINCREMENT, "                  + LONGITUDE   + " INTEGER,"                  + LATITUDE    + " INTEGER,"                  + TIME        + " INTEGER,"                 + TRACK_ID_FK + " INTEGER"                 + " );"               );      ... } 

Answer 1

Foreign key constraints with on delete cascade are supported, but you need to enable them.
I just added the following to my SQLOpenHelper, which seems to do the trick.

@Override public void onOpen(SQLiteDatabase db) {     super.onOpen(db);     if (!db.isReadOnly()) {         // Enable foreign key constraints         db.execSQL("PRAGMA foreign_keys=ON;");     } } 

I declared my referencing column as follows.

mailbox_id INTEGER REFERENCES mailboxes ON DELETE CASCADE