• 2022-06-03
    “把查询SC表和更新SC表的grade列的权限授予用户user”的正确SQL语句是( )。
    A: GRANT SELECT sc.UPDATE sc.grade TO user
    B: GRANT SELECT,UPDATE(grade)ON TABLE sc TO user
    C: GRANT SELECT,UPDATE ON TABLE sc.grade TO user
    D: GRANT SELECT ON TABLE sc,UPDATE ON TABLE sc(grade)TO user
  • B

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      【单选题】下列SQL语句中,能够实现“将查询SC表的权限授予用户U1,并且允许该用户将此权限授予其他用户”这一功能的是()。 A. GRANT SELECT TO SC ON U1 WITH PBULIC; B. GRANT SELECT ON SC TO U1 WITH PUBLIC; C. GRANT SELECT TO SC ON U1 WITH GRANT OPTION; D. GRANT SELECT ON SC TO U1 WITH GRANT OPTION;

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      ‏检索选修课程“C2”的学生中成绩最高的学生的学号。正确的SELECT语句是()。‍ A: SELECT SNO FROM SC WHERE CNO='C2' AND GRADE >= ( SELECT GRADE FORM SC WHERE CNO='C2' ); B: SELECT SNO FROM SC WHERE CNO='C2' AND GRADE IN ( SELECT GRADE FORM SC WHERE CNO='C2' ); C: SELECT SNO FROM SC WHERE CNO='C2' AND GRADE NOT IN ( SELECT GRADE FORM SC WHERE CNO='C2' ); D: SELECT SNO FROM SC WHERE CNO='C2' AND GRADE >= ALL ( SELECT GRADE FORM SC WHERE CNO='C2' );

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      检索选修课程"C2”的学生中成绩最高的学生的学号,正确的SELECT语句是______。 A: SELECT S# FORM SC WHERE C#="C2"AND GRADE>=(SELECT GRADE FORM SC WHERE C#="C2") B: SELECT S# FORM SC WHERE C#="C2"AND GRADE IN(SELECT GRADE FORM SC) WHERE C#="C2" C: SELECT S# FORM SC WHERE C#="C2"AND GRADE NOT IN(SELECT GRADE FORM SC WHERE C#="C2") D: SELECT S# FORM SC WHERE C#="C2"AND GRADE>=ALL(SELECT GRADE FORM SC WHERE C#="C2")

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      已知关系模式:sc(sno,sname,grade),各属性含义依次为学号、课程名、分数。要查找“数据库”课分数最高的学生的学号,正确的SQL语句是 A: SELECT sno FROM sc WHERE sname = "数据库" AND grade = MAX(grade) B: SELECT sno FROM sc FOR sname = "数据库" OR grade>=MAX(grade) C: SELECT sno FROM sc WHERE sname = "数据库" AND grade = (SELECT MAX(grade) FROM sc) D: SELECT sno FROM sc FOR sname = "数据库" OR grade = (SELECT MAX(grade) FROM sc)

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      检索选修了课程”C1”的学生中成绩最高的学生的学号,正确的SELECT语句为( ) A: SELECT Sno FROM SC WHERE Cno=’C1’ AND GRADE >=ALL (SELECT Grade FROM SC WHERE Cno=’C1’); B: SELECT Sno FROM SC WHERE Cno=’C1’ AND GRADE IN (SELECT Grade FROM SC WHERE Cno=’C1’); C: SELECT Sno FROM SC WHERE Cno=’C1’ AND GRADE > ANY (SELECT Grade FROM SC WHERE Cno=’C1’); D: SELECT Sno FROM SC WHERE Cno=’C1’ AND GRADE >= (SELECT Grade FROM SC WHERE Cno=’C1’);