Given the following table definitions: EMPLOYEE ID NAME DEPTID 01Smith 10 02Bossy 20 03 20 Peterson 04Goss 30 05Pape 40 06Avery 50 07O'Neal 60 08Carter 50 DEPARTMENT ID DEPTNAME 05 Hardware 10 Kitchen 20 Shoes 30 Toys 40 Electronics 50 Automotive and the following query: SELECT e.id, d.deptname FROM employee e, department d WHERE e.deptid = d.id AND e.id > 4 Which of the following queries will produce the same result set as the query above?()
A. SELECT e.id, d.deptname FROM employee e, department d WHERE e.id > 4
B. SELECT e.id, d.deptname FROM employee e INNER JOIN department d ON e.deptid = d.id WHERE e.id > 4
C. SELECT e.id, d.deptname FROM employee e FULL OUTER JOIN department d ON e.id = d.id WHERE e.id > 4
D. SELECT e.id, d.deptname FROM employee e LEFT OUTER JOIN department d ON e.deptid = d.id WHERE e.id > 4 UNION ALL SELECT e.id, d.deptname FROM employee e RIGHT OUTER JOIN department d ON e.deptid = d.id WHERE e.id > 4
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在一个无向图中,所有顶点的度数之和等于所有边数的(B)倍,在一个有向图中,所有顶点的入度之和等于所有顶点出度之和的()。
A. 1/2
B. 2
C. 1
D. 4