sql - Understanding correlation in mysql -

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i have table duplicate ids representing person has placed order. each of these orders has date. each order has status code 1 - 4. 4 means cancelled order. using following query:

select     personid, max(date), status     orders     status = 4 group     personid

the problem is, while return unique record each person recent order date, not give me correct status. in other words, assumed status correctly correlated max(date) , not. pulls, seemingly @ random, 1 of statuses 1 of orders. can add specificity say, in basic terms, give me exact status same record whatever max(date) is.

unfortunately, there no simple way want. other rdbms vendors don't consider queries using aggregate functions valid unless non-aggregated result fields in group by. general solution these kinds of questions involves subquery "last" records, joined original table rows.

depending on structure of data may or may not possible. instance, if have multiple rows same personid , date there no way determine alone one's status should used.


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