tee 2025_10_1_sql_log.txt

DROP SCHEMA IF EXISTS tinker;
CREATE SCHEMA tinker;
USE tinker;

CREATE TABLE s2
SELECT * FROM toyu.student;

SELECT *
FROM s2;

CREATE TEMPORARY TABLE s3
SELECT * FROM toyu.student;

SELECT *
FROM s3;

CREATE TABLE s4 LIKE toyu.student;

SELECT *
FROM s4;

INSERT INTO s4
SELECT * FROM toyu.student;

SELECT *
FROM s4;

SHOW TABLES;

-- Note that keys and constraints of student are missing in s2 and S3.
DESC student;
DESC s2;
DESC s3;
DESC s4;

DROP TABLE s2;
DROP TABLE s3;
DROP TABLE s4;

SHOW TABLES;

DROP SCHEMA IF EXISTS tinker;

INSERT INTO student VALUES
   (100010,'Bun','Yue',null,null,50,null),
   (100011,'Paul','Harris','CSCI','ITEC',23,1015);
  
SELECT * FROM student;
  
INSERT INTO student VALUES
   (100010,'Bun','Yue',null,null,50,null),
   (100011,'Paul','Harris','CSCI','ITEC',23,1015);
  
INSERT INTO student VALUES  
   (100020,'Bunno','Yue','GEOG',null,50,null);
INSERT INTO student VALUES  
   (100021,'Bunna','Yue',null,'GEOG',50,null);
INSERT INTO student VALUES  
   (100022,'Bunno','Yue',null,null,50,8888);

  
-- Remove the two new rows.
DELETE FROM Student
WHERE stuId = 100010 OR stuId = 100011;

SELECT * FROM student;

UPDATE student
SET major = 'CINF'
WHERE stuId = 100009;


UPDATE student
SET major = 'CINF';

DELETE FROM Student;

SELECT COUNT(*)
FROM student;


SELECT COUNT(*) INTO @count
FROM student;

SELECT *
FROM student;

SELECT * INTO @s
FROM student;

SELECT stuId INTO @s
FROM student;

-- operators:
-- student with credits in a range: including the lower and upper limits.
SELECT DISTINCT *
FROM Student
WHERE ach BETWEEN 30 AND 70;

SELECT DISTINCT *
FROM Student
WHERE 30 < ach AND  ach < 70;

SELECT DISTINCT *
FROM Student
WHERE ach BETWEEN 20 AND 40;

SELECT DISTINCT *  -- not the same
FROM Student
WHERE 20 < ach AND  ach < 40;

SELECT DISTINCT *
FROM Student
WHERE 20 <= ach AND  ach <= 40;