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create table DATA_IMPORT (LEARNER_ID number, USER_ID varchar2(30), ERROR_FLAG varchar2(1), IMPORT_NOTIFICATION varchar2(200));
insert into DATA_IMPORT (LEARNER_ID, ERROR_FLAG)
select 1, 'N' from dual
union all
select 2, 'N' from dual
union all
select 2, 'N' from dual
union all
select 3, 'Y' from dual
union all
select null, 'N' from dual
union all
select null, 'N' from dual;
6 rows affected
SELECT COUNT (D.LEARNER_ID), D.LEARNER_ID
FROM DATA_IMPORT D
-- WHERE D.USER_ID IN (SELECT S.OSUSER
-- FROM V$SESSION S
-- WHERE S.SID IN (SELECT DISTINCT V.SID
-- FROM V$MYSTAT V))
-- sys views not visible here
WHERE 1=1
AND D.ERROR_FLAG = 'N'
AND D.LEARNER_ID <> NULL
HAVING COUNT (D.LEARNER_ID) > 1
GROUP BY D.LEARNER_ID;
SELECT COUNT (D.LEARNER_ID), D.LEARNER_ID
FROM DATA_IMPORT D
-- WHERE D.USER_ID IN (SELECT S.OSUSER
-- FROM V$SESSION S
-- WHERE S.SID IN (SELECT DISTINCT V.SID
-- FROM V$MYSTAT V))
-- sys views not visible here
WHERE 1=1
AND D.ERROR_FLAG = 'N'
AND D.LEARNER_ID IS NOT NULL
HAVING COUNT (D.LEARNER_ID) > 1
GROUP BY D.LEARNER_ID;
| COUNT(D.LEARNER_ID) | LEARNER_ID |
|---|---|
| 2 | 2 |
SELECT COUNT (D.LEARNER_ID), D.LEARNER_ID
FROM DATA_IMPORT D
-- WHERE D.USER_ID IN (SELECT S.OSUSER
-- FROM V$SESSION S
-- WHERE S.SID IN (SELECT DISTINCT V.SID
-- FROM V$MYSTAT V))
-- sys views not visible here
WHERE 1=1
AND D.ERROR_FLAG = 'N'
-- AND D.LEARNER_ID IS NOT NULL
HAVING COUNT (D.LEARNER_ID) > 1
GROUP BY D.LEARNER_ID;
| COUNT(D.LEARNER_ID) | LEARNER_ID |
|---|---|
| 2 | 2 |
SELECT COUNT (*), D.LEARNER_ID
FROM DATA_IMPORT D
-- WHERE D.USER_ID IN (SELECT S.OSUSER
-- FROM V$SESSION S
-- WHERE S.SID IN (SELECT DISTINCT V.SID
-- FROM V$MYSTAT V))
-- sys views not visible here
WHERE 1=1
AND D.ERROR_FLAG = 'N'
AND D.LEARNER_ID IS NOT NULL
HAVING COUNT (*) > 1
GROUP BY D.LEARNER_ID;
| COUNT(*) | LEARNER_ID |
|---|---|
| 2 | 2 |
SELECT COUNT (*), D.LEARNER_ID
FROM DATA_IMPORT D
-- WHERE D.USER_ID IN (SELECT S.OSUSER
-- FROM V$SESSION S
-- WHERE S.SID IN (SELECT DISTINCT V.SID
-- FROM V$MYSTAT V))
-- sys views not visible here
WHERE 1=1
AND D.ERROR_FLAG = 'N'
-- AND D.LEARNER_ID IS NOT NULL
HAVING COUNT (*) > 1
GROUP BY D.LEARNER_ID;
| COUNT(*) | LEARNER_ID |
|---|---|
| 2 | null |
| 2 | 2 |