Could you please suggest me which version is good and Why?

Question

I have same program but names different, but with different selects and different logic ( for perfromance tuning). I mean below three resembles to same program took different timings in se30:
Which one is the BEST ;
Program  YKRAR232 took :
  ABAP                                                 1,875,565  =  54.1%
  Database                                                 1,479,609  =  42.6%
    System                                                   114,485  =   3.3%
                                                              3,469,659  = 100,0%
Program ZKRAR232 took :
     ABAP                                                   482,858  =  12.5%
Database                                                 3,303,617  =  85.7%
   System                                                    66,941  =   1.7%
                                                                3,853,416  = 100,0%
Program YJV_ZKRAR232 took :
     ABAP                                                   529,327  =  32.5%
Database                                                 1,004,661  =  61.7%
   System                                                    94,538  =   5.8%
                                                               1,628,526  = 100,0%
THANKS IN ADVANCE

Answer 1

Because of the buffering issue, it's difficult to give a good answer. If you just look at run times of database selects, you have to leave enough time between runs for the buffers to be refreshed. Instead, you might want to use transaction ST05 (performance analysis). You can use the explain function on each select to see how efficient (or not) it is. The results returned are calculated by the database and buffering is not an issue. But it may be difficult to compare differnt programs because you may end up trying to compare a lot of selects using a little time each against another larger select that takes longer.
For strictly ABAP processing, this isn't a problem.
What I would do is run each program a number of times one after the other and compare programs based on the least run time of each.
Performance tuning is as much art as science and there are other things to consider as well. For example, a highly tuned program will likely have more code and be more difficult to read and maintain. If the performance savings aren't that great, I would go with the simple program.
Rob