Search code examples
sqlmysqloperators

The "-" Operator in SQL where condition

I am encountering a rather peculiar syntax in MySQL, specifically the presence of a '-' symbol within the WHERE condition in the following query.

SELECT 
    users.id
FROM
    users
WHERE
    users.account_status >= 3
        AND users.account_status NOT IN (8 , 9)
        AND - users.registration_status = 14
        AND users.id IN (229);

I've researched this syntax in here?

Could it possibly indicate a transformation of the value of the 'registration_status' column into a negative number?

Solution

  • It's the unary minus operator. The following expressions are all equivalent:

    • - users.registration_status = 14
    • 0 - users.registration_status = 14
    • users.registration_status = -14

    with the latter probably being the most obvious (code clarity is important!)