CREATE TABLE Students (
student_name CHAR(50),
direction_of_study CHAR(50),
course INT,
education_level CHAR(50),
internship CHAR(50)
);
CREATE TABLE Prac (
direction_of_study CHAR(50),
course INT,
internship_type CHAR(50),
internship_location CHAR(50)
);
INSERT INTO Students (student_name, direction_of_study, course, education_level, internship)
VALUES
('Marat', 'IS', 2, 'bak', 'web'),
('Adam', 'VT', 2, 'bak', 'sysadmin'),
('Sam', 'IS', 1, 'mag', 'backend'),
('Marat', 'IS', 1, 'bak', 'frontend'),
('Simon', 'VT', 2, 'mag', 'sysadmin'),
('Marat', 'VT', 1, 'bak', 'frontend');
INSERT INTO Prac (direction_of_study, course, internship_type, internship_location)
VALUES
('IS', 2, 'web', 'bank'),
('VT', 2, 'sysadmin', 'tech company'),
('IS', 1, 'backend', 'tech company'),
('IS', 1, 'frontend', 'tech company'),
('VT', 3, 'sysadmin', 'bank'),
('VT', 1, 'bak', 'frontend');
SELECT student_name
FROM Students
INNER JOIN Prac ON Students.direction_of_study = Prac.direction_of_study AND Students.course = Prac.course
WHERE Students.direction_of_study = 'VT'
AND Students.course = 2
AND Prac.internship_location = 'tech company';
SELECT DISTINCT internship_type, internship_location
FROM Prac
WHERE direction_of_study = 'IS';
SELECT COUNT(DISTINCT internship_location) AS company_count
FROM Prac;
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