Experiment on performance: SELECT SINGLE vs FOR ALL ENTRIES

Posted on by Kerem Kayacan
Experiment on performance series

Part I: SELECT SINGLE vs FOR ALL ENTRIES

Part II: SELECT SINGLE vs FOR ALL ENTRIES, secondary index access

When all business requirements are met in a development, customer complaints always come down to performance. “Can’t this run any faster?” we always hear. Performance, in a technical point of view, is a broader concept that not just includes execution time, but also optimal use of system resources like memory and network load.  But powerful hardware of our age and requirement of end user satisfaction leaves us with a single option to have execution time (or speed) as the top priority performance aspect. So I will experiment on some known techniques for database access and internal table processing, and share the results here. Continue reading “Experiment on performance: SELECT SINGLE vs FOR ALL ENTRIES” →

ABAP by numbers: Length of decimal type

Posted on by Kerem Kayacan

Inequality between length and maximum digit count of packed decimal type causes great confusion even among seasoned developers. ABAPDOCU explains the relation with a fairly complicated formula:

Depending on the field length len and the number of decimal places dec, the following applies to the value range: (-10^(2len-1) +1) / (10^(+dec)) to (+10^(2len-1) -1) /(10^(+dec)) in increments of 10^(-dec)

Continue reading “ABAP by numbers: Length of decimal type” →

Obligatory selection screen parameters

Posted on by Kerem Kayacan

Almost every ABAP developer comes to a point where they require obligatory parameters along with user command logic in their selection screens. As you might already know, that’s a problem. Because obligatory parameters demand input on every action of user and interfere with user command logic, which results in a broken selection screen. Let’s see an example. Continue reading “Obligatory selection screen parameters” →