Adopted Bitmap

The base class Bmap.Person defines persons within an organization distributed
by various countries. All records are indexed by (Country, PersonalId).
this structure doesn't allow use of bitmaps.

So a wrapper class Bmap.PersonQ around the data eliminates the top level of
the index (Country) and isolates the PersonalId (%Integer, MINVAL=1).
We are ready to use a Bitmap index.

A few performance figures on 300010 generated records.
You see that Relative Cost are sometimes quite misleading.

base

  select count(*) from Bmap.Person  
  300010 global references 1600446 lines executed   

demo 1

  select count(*) from Bmap.Person where Ctry='RU'  
  Relative cost = 197762  
  10015 global references 70474 lines executed    

select count(*) from Bmap.PersonQ where Bmap.Ctry('RU')=1
Relative cost = 401400
10 global references 424 lines executed

demo2

  select count(*) from Bmap.Person   
     where Ctry='RU' and home_state='MA'   
  Relative cost = 457.96    
  218 Global references 2335 lines executed   

select count(*) from Bmap.PersonQ
where Bmap.Ctry('RU')=1 and home_state='MA'
Relative cost = 2012.8
16 global references 478 lines executed

demo3

  select home_state,count(*) from Bmap.Person   
     where Ctry='RU' group by home_state  
  Relative cost = 372162   
  Row count: 50 Performance: 0.027 seconds   
  10420 global references 153708 lines  

select home_state,count(*) from Bmap.PersonQ
where Bmap.Ctry('RU')=1 group by home_state
Relative cost = 453400
Row count: 50 Performance: 0.018 seconds
817 global references 155475 lines executed

GitHub