Given the following table definitions:EMPLOYEEID NAME DEPTID01Smith 1002Bossy 2003 20Peterson04Goss 3005Pape 4006Avery 5007O‘Neal 6008Carter 50DEPARTMENT ID DEPTNAME05 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 > 4Which 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
第1题:
MySQL中用DROP语句可删除数据库和数据表,以下哪句是正确的语法?()
A、DROPTABLEtable_name1
B、DROPTABLEtable_name1,table_name2
C、DROPTABLEIFEXISTStable_name1
D、DROPDATABASEDBname1
第2题:
设有员工实体Employee(employeeID,name,sex,age,tel departID),其中employeeID为员工号,name为员工姓名,sex为员工性别,age为员工年龄, tel为员工电话,记录该员工的手机号码、办公室电话等,deparID为员工所在部门号,参照另一部门实体Department的主码deparID。Employee实体中存在派生属性(67)。Employee实体中还存在多值属性(68)。对属性departID的约束是(69)。
A.name,原因是会存在同名员工
B.age,原因是用属性birth替换age并可计算age
C.tel,原因是员工有多个电话
D.departID,原因是实体Department已有departID
第3题:
设有员工实体Employee(employeeID,name,sex,age,tel,departID),其中employeeID为员工号,name为员工姓名,sex为员工性别,age为员工年龄,tel为员工电话,记录该员工的手机号码、办公室电话等,departID为员工所在部门号,参照另一部门实体 Department的主码departID。Employee实体中存在派生属性(40);Employee实体中还存在多值属性(41);对属性departID的约束是(42)。
A.name,原因是会存在同名员工
B.age,原因是用属性birth替换age并可计算age
C.tel,原因是员工有多个电话
D.departID,原因是实体Department已有departID
第4题:
A. M$LOG_TABLE_NAME
B. MLOG$_TABLE_NAME
C. MLOG_ TABLE_NAME
第5题:
第6题:
如果table_name表中有索引index_name,删除此索引的语句错误的是()。
A.DROP INDEX index_name ON talbe_name
B.ALTER TABLE table_name DROP INDEX index_name
C.DROP INDEX table_name.index_name
D.ALTER TABLE table_name DROP CONSTRAINT index_name