swasti

 Profile Answers by swasti 

• Mar 24th, 2009

 

Decode is faster than if-else

parag_tyagi2001

 Profile Answers by parag_tyagi2001 Questions by parag_tyagi2001

• Apr 14th, 2009

 

decode is much faster then If -Else because decode in built already have all the values of the column which we want to decode whereas in if - else statement  , we need to explicitly specify.

please anyone correct me

sanjeevlabh

 Profile Answers by sanjeevlabh Questions by sanjeevlabh

• Jan 22nd, 2010

 

The answer to this question would actually depend on the type of applicability of the usage that is being done. i.e. is it required in a query or in a PLSQL block. If it is in a query we cannot use if....else we will have to use decode. In a PLSQL block we can use if..else. However, for simple condition checking if..else is better in performance but for using this in sql we would have to use de-code.

In general decode does affect the performance of the query however, if we are using a function based index which has been built by using decode then it might actually be faster.

muraligrandhi

 Profile Answers by muraligrandhi 

• Jun 7th, 2010

 

DECODE is faster than IF-THEN-ELSE

REASON:
Decode is an Oracle built-in function, so no need to pass parameters to this function. Because all the parameters are internally defined but If-then-else statements we should define explicitly, so takes time for execution and converting into P-code.