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Posted on 2011-02-11
Medium Priority
Last Modified: 2012-05-11
I have three sample tables. All there has id field.
Why does it return duplicates accounts?

select a.field1, b.field1, c.field2
from table1 a
inner join table2 b
on a.id = b.id
inner join table3 c
on a.id = c.id
Question by:VBdotnet2005
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LVL 23

Assisted Solution

by:Rajkumar Gs
Rajkumar Gs earned 332 total points
ID: 34873770
If there are more records in table2 or table3 for a record in table1, INNER JOIN will return all the records
LVL 23

Accepted Solution

Rajkumar Gs earned 332 total points
ID: 34873796
For eg:-
If table1 have 1 record.
table2 have related 5 records
then INNER JOIN will return 5 records

Hope you are clear

Assisted Solution

Cboudroz earned 168 total points
ID: 34874064
because the id field is probably unique in each database or you don't have correct ON clause.


	employes e
	inner join function f
		on e.employe_id = f.employe_id 
	e.employe_id = 1

Open in new window

you will have two row for same employe if the employe got two different function in the compagnie.


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