Dynamic SQL substituting dynamic table name with slct statement having date

Question

Hello,
I just wanted some help with the following PL block. My problem is whenever I try to run this block it ask for invoking values for 2 substitute variables, though no substitute variables present in the code. Please find the code below:
Declare
cursor C_1 is
select unique table_name from gsi_daily_count;
table_names varchar2(240);
Begin
Open C_1;
Loop
Fetch C_1 into table_names;
EXIT WHEN C_1%NOTFOUND;
EXECUTE IMMEDIATE' select last_extract_date,
to_char(min(greatest(nvl(last_update_date,'||01-Jan-10||'),nvl(program_update_date,'||01-Jan-10||'))),'||DD-MON-YY HH24:MI:SS||') mi,
to_char(max(greatest(nvl(last_update_date,'||01-Jan-10||'),nvl(program_update_date,'||01-Jan-10||'))),'||DD-MON-YY HH24:MI:SS||') ma
from' || table_names ||'
group by last_extract_date
order by last_extract_date desc';
End Loop;
Close C_1;
COMMIT;
End;
Please help.
Thanks in advance.

Answer 1

You cannot specify your dates the way you have since they are being intepreted as bind variables:
Try this:
Declare
  cursor C_1 is
    select unique table_name
    from gsi_daily_count;
    table_names varchar2(240);
Begin
  Open C_1;
  Loop
    Fetch C_1 into table_names;
    EXIT WHEN C_1%NOTFOUND;
    EXECUTE IMMEDIATE' select last_extract_date,
                              to_char(
                                      min(
                                            greatest(
                                                      nvl(last_update_date,to_date('''|| '01-Jan-10' ||''',''dd-Mon-yy''))
                                                     ,nvl(program_update_date,to_date('''|| '01-Jan-10' ||''',''dd-Mon-yy''))
                                         ),''DD-MON-YY HH24:MI:SS''
                                     ) mi
                              to_char(
                                      max(
                                            greatest(
                                                      nvl(last_update_date,to_date('''|| '01-Jan-10' ||''',''dd-Mon-yy''))
                                                     ,nvl(program_update_date,to_date('''|| '01-Jan-10' ||''',''dd-Mon-yy''))
                                         ),''DD-MON-YY HH24:MI:SS''
                                     ) ma
                      from ' || table_names ||'
                      group by last_extract_date
                      order by last_extract_date desc';
  End Loop;
  Close C_1;
  COMMIT;
End;
/ There is not way for me to test this, so you may have to play around with all the quotes!