private void CreatePurchaseTable(SQLiteDatabase db)
{
db.ExecSQL("CREATE TABLE " + PURCHASE_HISTORY_TABLE_NAME + "(" + HISTORY_ORDER_ID_COL + " TEXT PRIMARY KEY, " + HISTORY_STATE_COL + " INTEGER, " + HISTORY_PRODUCT_ID_COL + " TEXT, " + HISTORY_DEVELOPER_PAYLOAD_COL + " TEXT, " + HISTORY_PURCHASE_TIME_COL + " INTEGER)");
db.ExecSQL("CREATE TABLE " + PURCHASED_ITEMS_TABLE_NAME + "(" + PURCHASED_PRODUCT_ID_COL + " TEXT PRIMARY KEY, " + PURCHASED_QUANTITY_COL + " INTEGER)");
}