通过 SQL,您如何按字母顺序选取 Persons 表中 LastName 介于 Adams 和 Carter 的所有记录?

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)

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

通过 SQL，从 "Actor" 表中选取 "FirstName" 列的值以 "a" 开头的所有记录的表述正确的是（ ）。 A: SELECT * FROM Actor WHERE FirstName='%a%' B: SELECT * FROM Actor WHERE FirstName='a' C: SELECT * FROM Actor WHERE FirstName LIKE '%a' D: SELECT * FROM Actor WHERE FirstName LIKE 'a%'