Is the order in which the conditions are given in the 'WHERE' clause are important?

Mean I heard from Oracle 8i onwards the order of where clause condition does not matter which oracle creates the explain plan...and execute..Is it true?

Questions by babhatti

Showing Answers 1 - 2 of 2 Answers

gtomar

  • Aug 7th, 2008
 

Hi,

Where Clause conditions execution are independent of order in explain plan but it reads top to bottom.

Thanks,
Gunjan

  Was this answer useful?  Yes

manoj_behera82

  • Aug 7th, 2008
 

Yes the order is important. But it is important for the performance of the query and not for the final result.
The output of the query will be the same irrespective of the order in which the join conditions are applied. Ideally the condition that filters maximum number of records should be placed last. Reason,  Oracle follows a bottom up approach.

Give your answer:

If you think the above answer is not correct, Please select a reason and add your answer below.