Oracle 11g Release 2

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

create table test
( data varchar2(200))
insert into test values('John/Bean/4000-M100')
1 rows affected

insert into test values ('John/4010-M100')
1 rows affected

insert into test values ('John/4003')
1 rows affected

insert into test values ('Sal_AS_180763852/4200009751_S5_154552/4023')
1 rows affected

select regexp_replace(data, '^.*/(\d{4})[^/]*$', '\1')
from test


REGEXP_REPLACE(DATA,'^.*/(\D{4})[^/]*$','\1')


4000

4010

4003

4023