Select only the records with same values - sql

Question

I am working on a SQL statement that will become a part of a view. What I need is to extract only the records that have the same unique key twice. The query looks like below right now.
select distinct
rscmaster_no_in, rsc_no_in, calendar_year, calendar_month,
Wstat_Abrv_Ch,
h.Wstat_no_in, Staffing_Calendar_Date, payhours,
l.OTStatus
from
vw_all_ts_hire h
left join
MCFRS_OTStatus_Lookup l on l.wstat_no_in = h.Wstat_no_in
where
rscmaster_no_in in (select rscmaster_no_in from vw_rsc_ECC_splty)
and Wstat_Abrv_Ch <> ''
and h.Wstat_no_in in (103, 107)
and l.OTStatus in ('ECCOTRemove', 'ECCOTSignup')
and Staffing_Calendar_Date = '2020-11-01' -- only for the testing purposes. Will be removed later.
order by
RscMaster_no_in
The result I get from the query above is:
I need to modify the SQL statement so that the end result is like below:
How can I modify the above statement to spit out the end result like that?

Answer 1

Use the analytic count(*) over () function.
with cte as (
select
count(*) over (partition by YourUniqueKey) as MyRowCount
{rest of your query}
)
select *
from cte
where MyRowCount = 2;

Answer 2

This should give you the results you want (performance is dependent on indexes/table design).
This takes your core logic and puts it into a sub select that only returns records that have a count > 1.
Then use those ID's to select all the data you need but only for those ID's that are in the sub select with count > 1
select distinct rscmaster_no_in,rsc_no_in, calendar_year, calendar_month,
Wstat_Abrv_Ch, h.Wstat_no_in, Staffing_Calendar_Date, payhours ,l.OTStatus
from vw_all_ts_hire h
left join MCFRS_OTStatus_Lookup l on l.wstat_no_in = h.Wstat_no_in
WHERE rscmaster_no_in IN (
SELECT rscmaster_no_in
from vw_all_ts_hire h
left join MCFRS_OTStatus_Lookup l on l.wstat_no_in = h.Wstat_no_in
where rscmaster_no_in in (select rscmaster_no_in from vw_rsc_ECC_splty)
and Wstat_Abrv_Ch <> ''
and h.Wstat_no_in in (103, 107)
and l.OTStatus in ('ECCOTRemove', 'ECCOTSignup')
and Staffing_Calendar_Date = '2020-11-01' -- only for the testing purposes. Will be removed later.
GROUP BY rscmaster_no_in
HAVING COUNT(*) > 1
)
order by RscMaster_no_in

Answer 3

You can use COUNT(*) OVER () window function such as
SELECT *
FROM
(
SELECT COUNT(*) OVER (PARTITION BY rscmaster_no_in) AS cnt,
t.*
FROM tab t
) t
WHERE cnt>1
AND OTStatus = 'ECCOTRemove'

Answer 4

This may help you :
select * from (
select distinct
rscmaster_no_in, rsc_no_in, calendar_year, calendar_month,
Wstat_Abrv_Ch,
h.Wstat_no_in, Staffing_Calendar_Date, payhours,
l.OTStatus,
SELECT COUNT(*) OVER (PARTITION BY rscmaster_no_in) AS uinqueCount
from
vw_all_ts_hire h
left join
MCFRS_OTStatus_Lookup l on l.wstat_no_in = h.Wstat_no_in
where
rscmaster_no_in in (select rscmaster_no_in from vw_rsc_ECC_splty)
and Wstat_Abrv_Ch <> ''
and h.Wstat_no_in in (103, 107)
and l.OTStatus in ('ECCOTRemove', 'ECCOTSignup')
and Staffing_Calendar_Date = '2020-11-01' -- only for the testing purposes. Will be removed later.
) innerReult
where uinqueCount=2 --Or uinqueCount>1 base on your business
order by
RscMaster_no_in