hello i would like to create average length time for each day.
i have following sql :
select left(entry_date,10) as datum
,round(avg(TIMESTAMPDIFF(SECOND,entry_date,modify_date)),0) as dlzka
from vicidial_list
where entry_date is not NULL and left(entry_date,7)="2016-07" and list_id="490" and avg(TIMESTAMPDIFF(SECOND,entry_date,modify_date))<1000
group by left(entry_date,10) asc;
can anybody please give me a hint?
Thanks