mysql - sql query comparing values -

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it's sql question found when i'm preparing interview.

how can efficiently find records value bigger previous one's?

id      1   2   3    4   5     value   6   5   10   8   30

you use self join this. long question compare current record previous record (and not previous records).

select     t1.*     table t1     inner join table t2         on t1.id = t2.id + 1        t1.value > t2.value

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