How to Work Around MySQL's Lack of EXCEPT Clause Functionality?

Syntax Error: EXCEPT Clause in Query

While composing a MySQL query that included an EXCEPT clause, you may encounter an error, specifically "You have an error in your SQL syntax." This error arises because MySQL does not support the EXCEPT syntax natively.

To overcome this limitation, consider utilizing alternative approaches. One method is to employ the NOT IN operator:

SELECT s.sno
FROM students s
WHERE s.sno NOT IN (
    SELECT t.sno
    FROM take t
    WHERE t.cno = 'CS112'
);

Alternatively, you can use a LEFT JOIN:

SELECT s.sno
FROM students s
    LEFT JOIN take t ON s.sno = t.sno
WHERE IFNULL(t.cno, '') != 'CS112'

These alternative queries achieve the same result: retrieving the sno values from the students table that are not present in the take table where cno equals 'CS112'.

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