1 # Query student in Article 2 to 4 data 2 the SELECT * the FROM student limit 1 , 4 ; 3 4 # query for all students to learn from the student table number, name and faculty 5 the SELECT the above mentioned id, `name`, Department the FROM student; . 6 . 7 # computer science students and English-based query from the student table . 8 the SELECT `name`, Department the fROM student the WHERE Department the iN ( ' computer Science ' , ' English department ' ); . 9 10 # student table query from the age of 18 - 22-year-old student information 11 The SELECT ID, `name`, Sex, 2019 - Birth the AS Age, Department, address the FROM student the WHERE 2019 - Birth the BETWEEN 18 is the AND 22 is ; 12 is 13 is # table query from a student how many people in each department 14 the SELECT Department, COUNT ( ID) the fROM Student the GROUP BY Department; 15 16 # query from the highest score for each subject Score table . 17 the SELECT c_name, MAX (Grade) the fROM Score the GROUP BY c_name; 18 is 19 # John Doe query test subjects 20 the SELECT c_name, Grade the FROM Score the WHERE stu_id = ( the SELECT the above mentioned id the FROM Student the WHERE name = ' John Doe ' ); 21 22 # query names of all students, faculty, subjects connected with the manner and test scores 23 the SELECT student.Id, `name`, Sex, Birth, Department, address, c_name, Grade the FROM student, score the WHERE student.id = score.stu_id; 24- 25 # calculate each student's total score of 26 the SELECT student. the above mentioned id, `name`, SUM (Grade)The FROM Student, Score the WHERE student.Id = score.stu_id the GROUP BY ID; 27 28 # calculates the average score for each test subject 29 the SELECT c_name, AVG (Grade) the FROM Score the GROUP BY c_name; 30 31 is # computer query score less than 95 student information points 32 the SELECT * the FROM student the WHERE ID the iN ( the SELECT stu_id the FROM Score the WHERE c_name = ' computer ' the AND Grade <95 ); 33 34 Student Information # inquiry also participate in computer and English test 35 the SELECT * the FROM Student the WHERE the above mentioned id = the ANY ( the SELECT stu_id the FROM Score the WHERE stu_id the IN ( the SELECT stu_id the FROM Score the WHERE c_name = ' computer ' ) the AND c_name = ' English ' ); 36 37 [ # computer sorted in descending examination results 38 is the SELECT stu_id, grade the FROM scoreThe WHERE c_name = ' computer ' the ORDER BY Grade DESC ; 39 40 # query from a student table and the score table school student number, and then merging the query results 41 is the SELECT ID the FROM student the UNION the SELECT stu_id the FROM score; 42 is 43 is # query or Zhang classmate Wang's name, department and test subjects and grades (suggesting, for example like fuzzy query keyword query to selec names beginning with a * from table name the WHERE name like 'a % ') 44 the SELECT student.Id, `name `, Sex, Birth, Department, Address, c_name, Grade the FROM Student, ScoreThe WHERE ( `name` the LIKE ' Zhang% ' OR ` name` the LIKE ' King% ' ) the AND student.id = score.stu_id; 45 46 # queries are students of Hunan's name, age, faculty and test subjects and grades 47 the SELECT student.Id, `name`, Sex, Birth, Department, the Address, c_name, Grade the FROM Student, Score the WHERE the Address the LIKE ' Hunan% ' the AND student.id = score.stu_id;