lock conflict on <str>

  Explanation:  The operation you attempted failed because another
  run  unit  is  holding  a lock in a mode that conflicts with the
  lock mode you needed.

  User Action:  Wait for  the  other  run  unit  to  finish.   Use
  ROLLBACK  or  COMMIT  to  release  all  your locks and retry the
  transaction, or specify that you want to wait on lock conflicts.