MariaDB 10.3

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select version();


version()


10.3.31-MariaDB


CREATE Table table_toteach (
	`teach-id` char(10),
	`teach` varchar(100),
	`teacher` varchar(100)
);
INSERT INTO table_toteach (`teach-id`,`teach`, `teacher`) VALUES
('1.0','Subj1-','Tname1'),
('1.2','Subj2-','Tname1');
('1.5','Subj3-','Tname1');
('2.0','Subj4-','Tname1');
CREATE TABLE table_students (
	student varchar(10)
);
INSERT INTO table_students (student) VALUES
('stname1'),
('stname2'),
('stname3'),
('stname4');
CREATE TABLE table_stpresents (
	student varchar(10),
	`Date` date,
	present varchar(10)
);
INSERT INTO table_stpresents (student,`Date`,present) VALUES
('stname5','2021-08-16','- yes -'),
('stname2','2021-08-16','- no -'),
('stname1','2021-08-17','- no -'),
('stname2','2021-08-17','- yes -'),
('stname1','2021-08-18','- yes -'),
('stname2','2021-08-18','- yes -');
('stname3','2021-08-19','- yes -');
('stname4','2021-08-19','- yes -');
('stname5','2021-08-19','- yes -');
CREATE TABLE table_timetable (
	`Date` date,
	subj1 varchar(50),
	subj2 varchar(50),
	subj3 varchar(50),
	stnames varchar(150)
);
INSERT INTO table_timetable (`Date`,subj1,subj2,subj3,stnames) VALUES
('2021-08-16','Subj1-','Subj2-','Subj3-','stname1, stname2, stname3'),
('2021-08-16','Subj1-','Subj3-','Subj2-','stname1, stname4, stname2'),
('2021-08-16','Subj1-','Subj2-','Subj3-','stname2, stname3, stname1'),
('2021-08-17','Subj2-','Subj1-','Subj3-','stname1, stname3, stname5'),
('2021-08-17','Subj2-','Subj1-','Subj1-','stname2, stname1, stname4'),
('2021-08-17','Subj1-','Subj4-','Subj2-','stname2, stname3, stname5'),
('2021-08-18','Subj1-','Subj3-','Subj2-','stname1, stname2, stname3'),
('2021-08-18','Subj4-','Subj2-','Subj1-','stname2, stname3, stname5'),
('2021-08-18','Subj3-','Subj1-','Subj4-','stname1, stname4, stname5');