now there is a usage time field, how to use group to group time periods, the grouping method is 0-10 minutes, 10-20 minutes 20-30 minutes, ask for advice.
now there is a usage time field, how to use group to group time periods, the grouping method is 0-10 minutes, 10-20 minutes 20-30 minutes, ask for advice.
Statistics by minute count , such as 2018-08-26 10:20:00 to 2018-08-26 10:29:59 through substr function 2018-08-26 10:2 , then group by .
for example, there is now a table with id int primary key and time datetime field. Then the statistical SQL is
SELECT count (id), SUBSTR (time,1,15) dt from table GROUP BY dt
what format is the usage time field?
datetime time point? Or int minutes?
refer to Mysql group query by time period to count the number of members
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