function testDeferrable_ExplicitTx_Insert_Error() {
  var childTable = db.getSchema().table('Child');
  var childRow = getSampleRows()[1];

  var tx = db.createTransaction();
  return tx.begin([childTable]).then(function() {
    var q1 = db.insert().into(childTable).values([childRow]);
    return tx.attach(q1);
  }).then(function() {
    return lf.testing.util.assertPromiseReject(203, tx.commit());
  });
}
Tests that a DEFERRABLE constraint violation during insertion, results in the
appropriate error when an explicit transaction is used.
@return {!IThenable}