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 DB2  |  Question 11 of 196    Print  
Explain an outer join?
An outer join includes rows from tables when there are no matching values in the tables.


  
Total Answers and Comments: 2 Last Update: September 02, 2008   
  
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August 11, 2006 05:00:11   #1  
       

RE: Explain an outer join. ?

suppose i have two tables emp(emp id, sal, isn) and stud(stud id, isn,total_mark).

now i join the two tables using outer join.

if i take sal from emp and total_mark from stud ,then after the join

all the rows from the stud table will be there where as only selected rows from emp as per the condition will be there.


 
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September 02, 2008 03:01:37   #2  
prasenjit_in Member Since: April 2008   Contribution: 18    

RE: Explain an outer join?
3 types.

Left outer Join----left table unmatched valyes are included.
Right Outer Join---right table unmatched values are included.
Full outer Join----Both table unmatched values are selected.

 
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Read Answers (2) | Asked by : sekhu_da


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