1.查詢Student表中的所有記錄的Sname、Ssex和Class列。
SELECT Sname,Ssex,Class FROM Students;
2.查詢教師所有的單位即不重復的Depart列。
SELECT DISTINCT Depart FROM Teachers;
3.查詢Student表的所有記錄。
SELECT * FROM Students;
4.查詢Score表中成績在60到80之間的所有記錄。
SELECT * FROM Scores WHERE Degree BETWEEN 60 AND 80;
5.查詢Score表中成績為85，86或88的記錄。
SELECT * FROM Scores WHERE Degree IN (85,86,88);
6.查詢Student表中“95031”班或性別為“女”的同學記錄。
SELECT * FROM Students WHERE Class='95031' OR Ssex='女';
7.以Class降序查詢Student表的所有記錄。
SELECT * FROM Students ORDER BY Class DESC;
8.以Cno升序、Degree降序查詢Score表的所有記錄。
SELECT * FROM Scores ORDER BY Cno,Degree DESC;
9.查詢“95031”班的學生人數。
SELECT COUNT(1) AS StuNum
FROM Students
WHERE Class='95031';
10.查詢Score表中的最高分的學生學號和課程號。
SELECT Sno,Cno FROM Scores ORDER BY Degree DESC LIMIT 1;
11.查詢‘3-105’號課程的平均分。
SELECT AVG(Degree)
FROM Scores
WHERE Cno='3-105';
12.查詢Score表中至少有5名學生選修的並以3開頭的課程的平均分數。
SELECT Cno,AVG(Degree)
FROM Scores
WHERE Cno LIKE '3%'
GROUP BY Cno
HAVING COUNT(Sno) >= 5;
13.查詢最低分大於70，最高分小於90的Sno列。
SELECT Sno
FROM Scores
GROUP BY Sno
HAVING MAX(Degree)<90 AND MIN(Degree)>70;
14.查詢所有學生的Sname、Cno和Degree列。
SELECT Sname,Cno,Degree
FROM Students INNER JOIN Scores
ON(Students.Sno=Scores.Sno)
ORDER BY Sname;
15.查詢所有學生的Sno、Cname和Degree列。
SELECT Sno,Cname,Degree
FROM Scores INNER JOIN Courses
ON(Scores.Cno=Courses.Cno)
ORDER BY Sno;