mysql except

MySQL does not have a built-in "EXCEPT" operator like some other database systems. However, you can achieve similar functionality using various techniques. One common approach is to use a combination of subqueries and the "NOT IN" or "NOT EXISTS" clauses.

Here's an example to illustrate how you can use the "NOT IN" clause to mimic the "EXCEPT" behavior:

SELECT column_name
FROM table1
WHERE column_name NOT IN (
    SELECT column_name
    FROM table2
);

This query will return all the values from `table1` that do not exist in `table2`.

Alternatively, you can use the "NOT EXISTS" clause to achieve the same result:

SELECT column_name
FROM table1
WHERE NOT EXISTS (
    SELECT column_name
    FROM table2
    WHERE table2.column_name = table1.column_name
);

Both of these queries will give you the same result as the "EXCEPT" operator in other databases. Just replace `column_name` with the actual column you want to compare in your tables.

Remember to adjust the table and column names according to your specific database schema.