Generating business summary stats in SQL dynamically, based on an inputted date
It is possible to simplify this:

CASE when prha.creation_date between to_date(:myDate,'DD-MON-YY') and to_date(:myDate,'DD-MON-YY') + 7  then 'Week 1'  
    when prha.creation_date between to_date(:myDate,'DD-MON-YY') + 7 and to_date(:myDate,'DD-MON-YY') + 14  then 'Week 2'  
    when prha.creation_date between to_date(:myDate,'DD-MON-YY') + 14 and to_date(:myDate,'DD-MON-YY') + 21 then 'Week 3' 
    when prha.creation_date between to_date(:myDate,'DD-MON-YY') + 21 and to_date(:myDate,'DD-MON-YY') + 28  then 'Week 4'  
  else 'After Month 1' END as "Req_Created",     1  as "Req Lines", 


In Oracle SQL, you can extract a date from the other date. Result is a number, which equals to day count between dates (fractional part is hours, minutes and seconds). So, prha.creation_date - to_date(:myDate,'DD-MON-YY') gives number of days, ceil((prha.creation_date - to_date(:myDate,'DD-MON-YY' - 1) / 7) gives number of week. Here is the code:

case when prha.creation_date - to_date(:myDate,'DD-MON-YY') &gt; 28 
       then 'After Month 1'
     else 'Week ' || ceil((prha.creation_date - to_date(:myDate,'DD-MON-YY') - 1) / 7)
     end as "Req_Created"


The following expression:

CASE when prha.authorization_status='APPROVED' then 1 else 0 END as "Approved Req"


could be replaced with decode function:

decode(prha.authorization_status, 'APPROVED', 1, 0) as "Approved Req"


decode is more brief, but has its own limitations. For more details, see documentation.