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Forum Newbie
Group: Forum Members
Last Login: 11/29/2008 4:04:39 AM
Posts: 5,
Visits: 17
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Hi,I need to compute a kpi named "Low-grade Silent Customers"
which means customers that haven't use our specific service for
3 months to 1 year.In our data warehouse,we store specific service
usage records in separate tables by month,and each table has more
than one hundred million recodes,who can give me a smart sql?
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Forum Guru
Group: Forum Members
Last Login: 8/20/2008 2:31:00 AM
Posts: 53,
Visits: 10
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hi,
Make use of union..
Regds,
sachin
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Forum Newbie
Group: Forum Members
Last Login: 11/29/2008 4:04:39 AM
Posts: 5,
Visits: 17
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thanks for your reply, sachin,
if i want to get the kpi of 200707,
do you mean i should do it like this :
select serv_id from serv_t
minus
(select serv_id from cdr_t where stat_month = 200707
union
select serv_id from cdr_t where stat_month = 200706
union
select serv_id from cdr_t where stat_month = 200705)
minus
(select serv_id from serv_t
minus
(select serv_id from cdr_t where stat_month = 200707
union
select serv_id from cdr_t where stat_month = 200706
......
union
select serv_id from cdr_t where stat_month = 200608)
)
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Supreme Being
Group: Forum Members
Last Login: 10/7/2008 6:20:30 PM
Posts: 136,
Visits: 11
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I believe Teradata Window Based function can address your problem.
Look up for OLAP functions in SQL reference manuals.
Thanks,
Vinay Bagare
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Forum Newbie
Group: Forum Members
Last Login: 11/29/2008 4:04:39 AM
Posts: 5,
Visits: 17
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Thank you,Vinay Bagare,I will find it right now.
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