下面代码的输出是什么?（） functionPerson(firstName,lastName){ this.firstName=firstName; this.lastName=lastName; } constlydia=newPerson("Lydia","Hallie"); constsarah=Person("Sarah","Smith"); console.log(lydia); console.log(sarah); A: Person{firstName:"Lydia",lastName:"Hallie"}andundefined B: Person{firstName:"Lydia",lastName:"Hallie"}andPerson{firstName:"Sarah",lastName:"Smith"} C: Person{firstName:"Lydia",lastName:"Hallie"}and{} D: Person{firstName:"Lydia",lastName:"Hallie"}andReferenceError

var person = {[br][/br] firstName: "Bill", lastName : "Gates", id : 648, fullName : function() { return this.firstName + " " + this.lastName; } }; 请问运行代码console.log(person.fullName())结果为______

您如何把 "Persons" 表中 "LastName" 列的 "Gates" 改为 "Wilson" ？ A: MODIFY Persons SET LastName='Wilson' WHERE LastName='Gates' B: UPDATE Persons SET LastName='Wilson' WHERE LastName='Gates' C: UPDATE Persons SET LastName='Wilson' INTO LastName='Gates' D: MODIFY Persons SET LastName='Wilson' INTO LastName='Gates'

通过 SQL，按字母顺序选取 Actor 表中 LastName 介于 Adams 和 Carter 的所有记录的表述正确的是（ ）。 A: SELECT * FROM Actor WHERE LastName BETWEEN 'Adams' AND 'Carter' B: SELECT * FROM Actor WHERE LastName>'Adams' AND LastName<'Carter' C: SELECT LastName>'Adams' AND LastName<'Carter' FROM Actor D: SELECT * FROM Actor WHERE LastName>'Adams' OR LastName<'Carter'

通过 SQL，您如何向 "Persons" 表中的 "LastName" 列插入 "Wilson" ？ A: INSERT INTO Persons (LastName) VALUES ('Wilson') B: INSERT ('Wilson') INTO Persons (LastName) C: INSERT INTO Persons ('Wilson') INTO LastName D: INSERT Persons (LastName) VALUES ('Wilson')

通过 SQL，向 "Actor" 表中的 "LastName" 列插入 "Wilson"表述正确的是（）。 A: INSERT INTO Actor (LastName) VALUES ('Wilson') B: INSERT INTO Actor ('Wilson') INTO LastName C: INSERT INTO Actor ('Wilson') INTO (LastName) D: INSERT ('Wilson') INTO Actor (LastName)

通过 SQL，您如何按字母顺序选取 Persons 表中 LastName 介于 Adams 和 Carter 之间（含其本身）的所有记录？ A: SELECT * FROM Persons WHERE LastName BETWEEN 'Adams' AND 'Carter' B: SELECT * FROM Persons WHERE LastName>'Adams' AND LastName C: SELECT LastName>'Adams' AND LastName

通过 SQL，您如何向 "Persons" 表中的 "LastName" 列插入 "Wilson" ？ A: INSERT INTO Persons (LastName) VALUES ('Wilson') B: INSERT ('Wilson') INTO Persons (LastName) C: INSERT INTO Persons ('Wilson') INTO LastName

关系模式Sailors(sid,lastname.firtname,age,ratring)，其中lastname允许为空. 下面哪个语句能够查找出lastname属性值不为空的水手信息. A: SELECT * FROM SAILORS WHERE LASTNAME<>’NULL’ B: SELECT * FROM SAILORS WHERE LASTNAME<>NULL C: SELECT * FROM SAILORS WHERE LASTNAME IS not NULL D: SELECT * FROM SAILORS WHERE LASTNAME not LIKE ’NULL’

在员工管理系统中，查询表employee表中所有员工的姓名，字段:id(int),firstname(varchar),lastname(varchar),以下sql语句正确的是（）。 A: Select firstname +’.’+ lastname as ‘name’ from employee B: Select firstname +’.’+ lastname from employee C: Select ‘name’= firstname +’.’+ lastname from employee D: Select firstname,lastname from employee