What are the ids of all employees that don't have certificates?
SELECT eid FROM Employee EXCEPT SELECT eid FROM Certificate
SELECT eid FROM Employee EXCEPT SELECT eid FROM Certificate
[{'eid': 15645489}, {'eid': 248965255}, {'eid': 254099823}, {'eid': 287321212}, {'eid': 310454877}, {'eid': 348121549}, {'eid': 486512566}, {'eid': 489221823}, {'eid': 489456522}, {'eid': 552455348}, {'eid': 619023588}]