JTable delete row with multi column key

Question

I'm try'n to delete a record using JTable delete() on a multi-column table. Table is a linked table defined as:

    CREATE TABLE IF NOT EXISTS  `#__bb_league_members` (
      `user_id` int(10) unsigned NOT NULL ,
      `league_id` int(10) unsigned NOT NULL ,
      `status` TINYINT NULL DEFAULT 0,
     ....
    PRIMARY KEY (`league_id`,`user_id`)
    )  ENGINE=InnoDB DEFAULT CHARSET=utf8;

since I have no single primary key, I can not use .delete($pk) but I have to load the record into a JTable instance.

        $data = [];
        $data['user_id'] = $uid;
        $data['league_id'] = $lid; 

        $tbl = $this->getTable('LeagueMember');
        $tbl->load($data); //a var dump here shows the record is loaded!!
        return $tbl->delete();

according to the Joomla 3.6 docu on JTable.delete($pk)

$pk is: "An optional primary key value to delete. If not set the instance property value is used."

So if I omit the $pk the current loaded instance should be deleted. However I get a "Null primary key not allowed." exception from my code above.

How do I delete a record with a multiple-column key?

PS: I know I can use a SQL statement directly, but my table classes are set up to do tracing/logging, and I would like to stick with using them.

Answer 1

After a little bit more digging I found a 2009 forum post here which states that JTable does not support multi-column or compound keys. :( So for now, I had to extend JTable with my own multi_column_key_delete() and ... update() functions