Mysql - ORDER BY - Can to use condition? -

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i sort list date_modified desc

this problem when new record input, date_modified null date 0000-00-00 00:00:00

so record in bottom, not top of list.

how sort ? :(

note: don't insert date_modified date , because have field date_create

order coalesce(date_modified, date_created) desc;

but, performance better if set date_modified current_timestamp when doing insert, suggested.


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