please explain this one
952526Sep 10 2012 — edited Sep 11 2012Hi, I relaly have trouble with the "date"
can anyone explains what the following is doing? Thanks
select trunc( DATE '1970-01-01' + timestamp / (1000 * 60 * 60 * 24) - 7/24) report_date,
count(*) route_request
from system_usage_load_api
where DATE '1970-01-01' + timestamp / (1000 * 60 * 60 * 24) >= '25-May-12'
and DATE '1970-01-01' + timestamp / (1000 * 60 * 60 * 24) < trunc(sysdate)
group by trunc( DATE '1970-01-01' + timestamp / (1000 * 60 * 60 * 24) - 7/24)