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one of the performance tuning techiques is join with database kept to a minimum. why?

  
Total Answers and Comments: 2 Last Update: March 26, 2009     Asked by: prabhupurna 
  
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October 28, 2006 05:05:49   #1  
K Vijay Kumar        

RE: one of the performance tuning techiques is join wi...

Performing join at database will improve the performance a lot.

take a scenario of joining between the two tables.

Usally we take two database components and place a join component to perform a join between them.This approach takes 2 hits to the data base to retrive the data and perform a join.

Instead of doing in this way we can write a query to perform a join at the database level by specifing the query while selecting the table. This approach takes only one hit to the data base.


 
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March 26, 2009 09:43:09   #2  
Subhra Dhar Member Since: March 2009   Contribution: 3    

RE: one of the performance tuning techiques is join with database kept to a minimum. why?
Join with Database (Join with DB) should not be used if number of records to be joined with a table is very high as it degrades performance. Better result can be achieved by retrieving the data from db table and using join component.

There should definitely be an index on the column for the where clause used in the join with db component.

 
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