Unable to append the output of for loop - linux

Question

I am trying to get tablespace total space for those tablespaces where given threshold is breached.
As I am getting more than one tablespaces in output , I am splitting those and after that running a for loop on array. Now I need to get bytes for each i but its only printing value of first occurrence. How should I append all the values?
Please check below code:
output1=`sqlplus -s username/password as sysbackup <<END1
set linesize 200
set head off
select tablespace_name||',' from dba_tablespace_usage_metrics where used_percent > 50;
exit;
END1`
IFS=', ' read -r -a array <<< $output1
for val in "${array[#]}"
do
output2=`sqlplus -s username/password as sysbackup <<END2
set serveroutput on;
set linesize 200
set head off
spool test.txt
SELECT TABLESPACE_NAME, ROUND (SUM (BYTES) / 1048576) FROM DBA_DATA_FILES WHERE TABLESPACE_NAME = '${array[val]}' GROUP BY TABLESPACE_NAME;
spool off;
#test.txt
exit;
END2`
done
#test.sql should print :
SYSAUX 2048
SYSTEM 4027
but its only printing:
SYSAUX 2048

Answer 1

Your code isn't printing anything from the loop at the moment; if you print $output2 after the loop then you'd see that value once; if you did it inside the loop then you'd see it multiple times, with the same value. Each output would also plus an SP-0734 error, which you may be supressing.
When you write to test.txt you're putting the result of the query against dba_data_files into that file; and $val has the value form the array not an index, so ${array[val]} doesn't mean what you probably think, and always gives you the first element in the array; so each time around the loop you've got the same result from the same query in test.txt.
Then you execute that, which gets an error. But both the initial query and that error is all being captured into output2 - just as you'd see it all if you ran test.txt manually. And that is overwritten each time. So if you process/display it inside the loop you'd see the same result repeated; if you ran it after the loop (which is what you seem to be doing, from your description) then you'd see it once.
If you really wanted to append the output each time around the loop you could do:
output2=${output2}`sqlplus -s username/password as sysbackup <<END2
...
END2`
or:
output2+=`sqlplus -s username/password as sysbackup <<END2
...
END2`
but you would need to clean up the output that both queries are producing, and then might need to include a newline in that concatenation.
This would be much simpler as a single query, which just outputs directly instead of to a variable:
sqlplus -s username/password as sysbackup <<END1
set pagesize 0
set linesize 200
set feedback off
SELECT TABLESPACE_NAME, ROUND (SUM (BYTES) / 1048576)
FROM DBA_DATA_FILES
WHERE TABLESPACE_NAME IN (
select tablespace_name
from dba_tablespace_usage_metrics
where used_percent > 50
)
GROUP BY TABLESPACE_NAME
ORDER BY TABLESPACE_NAME;
END1
If you don't want the column alignment then concatenate the name and size values:
SELECT TABLESPACE_NAME || ' ' || ROUND (SUM (BYTES) / 1048576)