Reverse the String without using reverse function

 WELCOME

 Expected Output:

EMOCLEW 

with t as (select 'WELCOME' d from dual)

select d from t connect by level <=length(d);

 

with t as (select 'WELCOME' d from dual)

select d,substr(d,level,1) from t connect by level <=length(d);

with t as (select 'WELCOME' d from dual)

select d,substr(d,level,1),level from t connect by level <=length(d);

 

 

with t as (select 'WELCOME' d from dual)

select listagg(s) within group (order by l) from

(select d,substr(d,level,1) s,level l from t connect by level <=length(d));

 

with t as (select 'WELCOME' d from dual)

select listagg(s) within group (order by l desc) from

(select d,substr(d,level,1) s,level l from t connect by level <=length(d));