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can any one explain the differences between left and Left outer join ? (In all Perspectives like performance etc...)
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lw@zi 3-Jan-14 3:35am
   
CPallini 3-Jan-14 3:38am
   
(virtual) 5.
coded007 3-Jan-14 4:02am
   
I know that d@nish but i didn't find any performance..... like this but it has it not clear
CPallini 3-Jan-14 3:39am
   
Don't be afraid of using Google or reading the documentation.
coded007 3-Jan-14 4:04am
   
I read some where it differs while inserting bulk data and searching BOL files. I need explanation for this
Jain Nishant 3-Jan-14 4:20am
   
Both of them are same...
thatraja 3-Jan-14 4:31am
   
Agree the above comment, no difference. Same
coded007 3-Jan-14 6:27am
   
Dear All, Please find the link with respect i have doubt

http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=100403
CHill60 3-Jan-14 15:33pm
   
Why does that link give you a doubt? Everyone there is saying there simply is no difference between the two. In terms of performance it will take you longer to type "left outer join" than to type "left join"
coded007 6-Jan-14 1:54am
   
so it is saying that there will be little bit change in terms of performance. am I right ?
CHill60 6-Jan-14 7:40am
   
Nowhere in the link http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=100403[^] could I find anything about a change in performance. There is no difference between 'left outer join' and 'left join'
coded007 6-Jan-14 9:24am
   
Please check the answer quoted by "Tharindu" he said that there will be a performance difference is it true ?
CHill60 6-Jan-14 13:39pm
   
No he has not. His English is quite poor but I believe he is saying that he cannot find out for definite, but hopes there is no performance difference. See the response immediately after from 'elancaster'. Tharindu did not post a solution, he posted a questionable comment
coded007 6-Jan-14 19:28pm
   
Ok then! Thanks for postings.......

   
Comments
Maciej Los 3-Jan-14 5:30am
   
+5!
TechNet of Microsoft wote:
SQL Server uses the following ISO keywords for outer joins specified in a FROM clause:
  • LEFT OUTER JOIN or LEFT JOIN
  • RIGHT OUTER JOIN or RIGHT JOIN
  • FULL OUTER JOIN or FULL JOIN


source: Using Outer Joins[^]

LEFT JOIN and LEFT OUTER JOIN has the same meaning to MS SQL server.

Here is an excellent article about joins: Visual Representation of SQL Joins[^] which ight help you to understand how it works!
   
v2
There is absolutely no difference between LEFT JOIN and LEFT OUTER JOIN. The same is true for RIGHT JOIN and RIGHT OUTER JOIN. When you use LEFT JOIN keyword in SQL Server, it means LEFT OUTER JOIN only.


Both are same. The word OUTER is optional

refer this:-
http://blog.sqlauthority.com/2009/04/13/sql-server-introduction-to-joins-basic-of-joins/[^]
   
Comments
Maciej Los 3-Jan-14 5:30am
   
+5!
TrushnaK 3-Jan-14 5:41am
   
thanks Maciej.....

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