How to append a column data to a MAX Aggregate function in SQL? -


column names: name, reading, channel, time

i'm trying find max value each distinct name. each name has many values read on time interval of once every hour. goal pick out max value each distinct name , record time interval occurred in.

so far have gotten code:

 select name, max(reading) "max_reading", data, channel, time   interval_data   group name, data, channel

however, gives me error saying time has aggregated or grouped by. there easy way append time max value occurred @ output , not have perform grouped by/aggregate function on column?

sample data:

name    reading     data    channel     time 1       1           1       1           1/15/2015 09:00 1       3           1       1           1/15/2015 10:00 1       2           1       1           1/15/2015 11:00 1       5           1       1           1/15/2015 12:00 2       2           1       1           1/15/2015 09:00 2       4           1       1           1/15/2015 10:00 2       6           1       1           1/15/2015 11:00 2       5           1       1           1/15/2015 12:00 3       7           1       1           1/15/2015 09:00 3       3           1       1           1/15/2015 10:00 3       5           1       1           1/15/2015 11:00 3       2           1       1           1/15/2015 12:00

desired output: (max reading each distinct name time when max reading reading occurred)

name    reading     data    channel     time 1       5           1       1           1/15/2015 12:00 2       6           1       1           1/15/2015 11:00 3       7           1       1           1/15/2015 09:00

without knowing how data , channel come play, use find data need each name's max(reading):

select     id.name, id.reading, id.data, id.channel, id.type      interval_data id join (     select          name, max(reading) reading              interval_data     group         name     ) id_agg     on      id.name = id_agg.name      ,      id.reading = id_agg.reading

if need channel , type distinguish unique row, include in inner-join sub-query , in join's on parameters.


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