You may use such a SQL Select statement for each substituted individual line
( Failure on table TOLL_USR_TRXN_HISTORY
in the below case )
from your text :
select regexp_replace(q.word, '[^a-zA-Z0-9_]+', '') as word
from
(
select substr(str,nvl(lag(spc) over (order by lvl),1)+1*sign(lvl-1),
abs(decode(spc,0,length(str),spc)-nvl(lag(spc) over (order by lvl),1))) word,
nvl(lag(spc) over (order by lvl),1) lg
from
(
with tab as
( select 'Failure on table TOLL_USR_TRXN_HISTORY' str from dual )
select instr(str,' ',1,level) spc, str, level lvl
from tab
connect by level <= 10
)
) q
where lg > 0
and upper(regexp_replace(q.word, '[^a-zA-Z0-9_]+', ''))
= regexp_replace(q.word, '[^a-zA-Z0-9_]+', '')
and ( nvl(length(regexp_substr(q.word,'_',1,1)),0)
+ nvl(length(regexp_substr(q.word,'_',1,2)),0)
+ nvl(length(regexp_substr(q.word,'_',1,3)),0)) > 0
and nvl(length(regexp_substr(q.word,'_',1,4)),0) = 0;