Performance issue when using select count on large tables

Question

Hello Experts,
I have a requirement where i need to get count of data  from a database table.Later on i need to display the count in ALV format.
As per my requirement, I have to use this select count inside a nested loops.
Below is the count snippet:
LOOP at systems assigning <fs_sc_systems>.
LOOP at date assigning <fs_sc_date>.
SELECT COUNT( DISTINCT crmd_orderadm_i~header )
   FROM crmd_orderadm_i
   INNER JOIN bbp_pdigp
       ON crmd_orderadm_iclient EQ bbp_pdigpclient               "MANDT is referred as client
     AND crmd_orderadm_iguid  EQ bbp_pdigpguid
     INTO w_sc_count
WHERE crmd_orderadm_i~created_at BETWEEN <fs_sc_date>-start_timestamp
     AND <fs_sc_date>-end_timestamp
     AND bbp_pdigp~zz_scsys   EQ <fs_sc_systems>-sys_name.
endloop.
endloop.
In the above code snippet,
<fs_sc_systems>-sys_name is having the system name,
<fs_sc_date>-start_timestamp is having the start date of month
and <fs_sc_date>-end_timestamp is the end date of month.
Also the data in tables crmd_orderadm_i and bbp_pdigp is very large and it increases every day.
Now,the above select query is taking a lot of time to give the count due to which i am facing performance issues.
Can any one pls help me out to optimize this code.
Thanks,
Suman

Answer 1

Hi Choudhary Suman ,
Try this:
SELECT crmd_orderadm_i~header
  INTO it_header                 " interna table
  FROM crmd_orderadm_i
INNER JOIN bbp_pdigp
    ON crmd_orderadm_iclient EQ bbp_pdigpclient
   AND crmd_orderadm_iguid   EQ bbp_pdigpguid
   FOR ALL ENTRIES IN date
WHERE crmd_orderadm_i~created_at BETWEEN date-start_timestamp
                                      AND date-end_timestamp
   AND bbp_pdigp~zz_scsys EQ date-sys_name.
    SORT it_header BY header.
    DELETE ADJACENT DUPLICATES FROM it_header
    COMPARING header.
    describe table it_header lines v_lines.
Hope this information is help to you.
Regards,
José