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If I do SELECT a AS b and b is not a column in the table, would query create the "virtual" column?

in fact, I need to incorporate some virtual column into the query and process some information into the query so I can use it with each item later on.

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Something like:

SELECT id, email, IF(active = 1, 'enabled', 'disabled') AS account_status FROM users

This allows you to make operations and show it as columns.

EDIT:

you can also use joins and show operations as columns:

SELECT u.id, e.email, IF(c.id IS NULL, 'no selected', c.name) AS country
FROM users u LEFT JOIN countries c ON u.country_id = c.id

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