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select distinct(empid),distinct(dept),name
from EMP
will the above query work?
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Answer / harsha
No, It will not work. SELECT DISTINCT works only for single
cloumn.
DISTINCT can be applied multiple times only when you want
to apply aggregate functions such as COUNT, AVG & SUM.
e.g.
SELECT COUNT(EMPNO)/COUNT(DISTINCT(WORKDEPT)), COUNT
(DISTINCT(JOB))
FROM DSN8810.EMP
| Is This Answer Correct ? | 14 Yes | 1 No |
Answer / chidambara subbu
No, It will not work. We can select DISTINCT values for
multiple columns however not all the columns will give
ditint value. For intance , see below table TABLE1
Name City
XXX Chennai
FFF HYD
XXX Blore
YYY Mumbai
1.SELECT DISTINCT NAME FROM TABLE1
Name
XXX
FFF
YYY
2. SELECT DISTINCT NAME,City FROM TABLE1
Name City
XXX Chennai
FFF HYD
XXX Blore
YYY Mumbai
See the result of second query. It has selected duplicate
entry 'XXX' in the Name column.
| Is This Answer Correct ? | 0 Yes | 0 No |
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