1. A computer-implemented method for inserting an object into a distributed database, comprising: at a computer system including one or more processors and memory storing one or more programs for execution by the one or more processors: receiving an object to be inserted into a priority queue, wherein the object includes a unique identifier and a priority; generating an index for the object; generating a row name for the object based on the index, the priority of the object, and the unique identifier of the object, wherein a lexicographical order of the row name for a higher priority object is smaller than the lexicographical order of the row name for a lower priority object; and inserting the object into a row of the distributed database using the row name.