mysql - SQL - Explode the dates between the ranges as new records -


i want perform explode kind of task in mysql, need create new records per day start , end dates.

current data looks this:

person, start date, end date, score     , 12/05/2017, 14/05/2017, 0.8     , 15/05/2017, 17/07/2017, 0.3 b     , 12/05/2017, 14/05/2017, 0.5 b     , 15/05/2017, 17/07/2017, 0.2

now, need re create data as

person, date,  score     , 12/05/2017, 0.8     , 13/05/2017, 0.8     , 14/05/2017, 0.8     , 15/05/2017, 0.3     , 16/05/2017, 0.3     , 17/05/2017, 0.3 b     , 12/05/2017, 0.5 b     , 13/05/2017, 0.5 b     , 14/05/2017, 0.5 b     , 15/05/2017, 0.2 b     , 16/05/2017, 0.2 b     , 17/05/2017, 0.2

since, joining tables other tables on date & person column, operation needed. how can in mysql?

you can this

select person, startdate + interval q.n - 1 day dates,score    table1 t cross join (    select a.n + b.n * 10 + 1 n           (select 0 n union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9)    ,(select 0 n union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) b     order n ) q   q.n - 1 <= datediff(enddate, startdate)   order pno, dates

the subquery generates sequence of numbers 1 100. can adjust needs (if date differences span more or less 100 days) or substitute persisted tally(numbers) table if lot of such queries.


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