MySQL IF NOT EXISTS / IFNULL SELECT other column -


i want check, if column (mysql) exists. if not, mysql should take value column exists. query looks this, not work:

if not exists (select `en` `hp_strings`                 `name`='copyright' , `group`='system')     select `default` `hp_strings`      `name`='copyright' , `group`='system';

i tried

ifnull((select `en` `hp_strings`          `name`='copyright' , `group`='system'), (select `default` `hp_strings`   `name`='copyright' , `group`='system'));

same result (error)

edit: 'en' not exist. want know, if exists.

to inspect table structure in mysql, have query information_schema database. that, db user must have access system database (which regular user shouldn't have).

i don't know trying do, should rethink database structure doesn't require checking if column exists in table.


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