如果经常执行类似于下面的查询语句SELECT * FROM STUDENT where substr(sname,0,2)=’陈’,应该为STUDENT表的SNAME列创建()索引。
select count(*) from student和select count(id) from student之间的区别是什么?
You need to give the MANAGER role the ability to select from, insert into, and modify existing rows in the STUDENT_GRADES table. Anyone given this MANAGER role should be able to pass those privileges on to others. Which statement accomplishes this? ()
Examine this statement: SELECT student_id, gpa FROM student_grades WHERE gpa > &&value; You run the statement once, and when prompted you enter a value of 2.0. A report is produced. What happens when you run the statement a second time?()
Examine the statement: GRANT select, insert, update ON student_grades TO manager WITH GRANT OPTION; Which two are true?()
Examine this statement: SELECT student_id, gpa FROM student_grades WHERE gpa >&&value; You run the statement once, and when prompted you enter a value of 2.0. A report is produced. What happens when you run the statement a second time?()
下列的SQL语句能实现的功能是( )。 SELECT*FROM仓库WHERE仓库号=”WH1” UNIONSELECT*FROM仓库WHERE仓库号=”WH2”
From SQL*Plus, you issue this SELECT statement: SELECT* FROM order; You use this statement to retrieve data from a data table for ().
SELECT * FROM Student INNER JOIN SC ON Student.Sno = SC.Sno语句可将Student与 SC连接起来。
SELECT * FROM Student WHERE Sname LIKE ’[张李刘]%’ 语句可以查找姓张、李、刘的学生。
语句“SELECT * FROM 成绩表 WHERE 成绩>(SELECT avg(成绩) FROM 成绩表)”的功能是查询成绩表中所有成绩大于平均成绩的记录。
有如下的SQL语句。Ⅰ. SELECT sname FROM s,sc WHERE grade<60Ⅱ. SELECT sname FROM s WHERE sno IN(SELECT sno FROM sc WHERE grade<60)Ⅲ.SELECT sname FROM s,sc WHERE s.sno=sc.sno AND grade<60若要查找分数(grade)不及格的学生姓名(sname),则以上正确的有哪些?( )
有学生信息表 student,求年龄在 20-22岁(含 20 岁和22岁)的学生姓名和年龄的SQL语句是:SELECT sname,age FROM student WHERE age_____ 。
有如下SQL语句:SELECT * FROM 仓库 WHERE 仓库号=“H1”;UNION;SELECT * FROM 仓库 WHERE 仓库号=“
A.SELECT TOP 1 pNanme,price FROM products ORDER BY price B.SELECT pName,MAX(price) FROM products C.SELECT pName,MAX(price) FROM products GROUP BY pName D.SELECT pName,price FROM products WHERE price=(SELECT MAX(price) FORM products) 此题为多项选择题。
可以使用select top 3*from student 查询前3条记录。
有如下SQL语句: SELECT*FROM 仓库 WHERE 仓库号=“H1”; UNION; SELECT*FROM 仓库 WHERE 仓库号=“H2” 该语句的功能是
BookStore数据库中有订单表Order(OrderCode, CustomerCode, TotalPrice, Address, OrderTime, OrderStatus)查询订单总价(TotalPrice)在100到200元之间的订单信息。SQL语句:SELECT OrderCode, TotalPrice, OrderTime, OrderStatus FROM [Order]WH
8、在student和sc表中查找选修002课程号的学生姓名,查询语句如下 Select sname from student,sc where student.sno=sc.sno and cno=”002” 如果student表有1000条学生记录,SC表有5000条选课记录,符合要求的选课记录有50条,一个块能装10条学生记录或100条选课记录,内存中留出10块用于存放选课记录、留出一块用于存放学生记录。 如果按照笛卡尔乘积-选择-投影的过程执行,如果一个块可以装10条连接结果记录,则在选择阶段需要读取的块数是多少?
下面()语句和“select * from student where sex=’男’&& age=20;”语句查询出的结果是一样的。
SELECT * FROM Student WHERE Sname LIKE'[张李刘]%' 语句可以查找姓张、李、刘的学生。()
设有一个关系Student(学号,姓名,系名,课程号,成绩),查询至少选修了四门课程的学生学号、姓名及平均成绩的SELECT语句应该是:SELECT学号,姓名,AVG(成绩)AS平均成绩FROM StudentGROUP BY()HAVING()
有如下存储过程: CREATE PROCEDURE up_studentInfo() BEGIN SELECT * FROM student WHERE b
10、以下触发器,在________情况下不会被触发。 CREATE TRIGGER tri_StudentInsDel ON Student FOR INSERT, UPDATE AS SELECT * FROM Student