SQL Query with Typo not working in MySQL (Order by on calculated field) -

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i have query in 1 of column calculated one. every thing working except not ordering results when use calculated column in query. query large 1 have simplified below understanding. here calculated column "remaining"

select t1.id, t1.name, t2.duration - datediff(now(), t1.posting_time) "remaining"   table1 t1, table2 t2  td.id = t1.timefield  order id, name, remaining desc

even if remove "remaining" order clause or use asc or desc, nothing happens , order stays same.

the time when 'remaining' alters sort order when id , name in 2 rows same. otherwise, has no effect on ordering.

you need fix typo of 'td.id' 't2.id'.

you should learn join notation too:

select t1.id, t1.name, t2.duration - datediff(now(), t1.posting_time) "remaining"   table1 t1   join table2 t2 on t2.id = t1.timefield  order id, name, remaining desc

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