Remove a random expression from string

Question

I have a string/column something like this

String a = \"000003023_AggregateStopLossLimit_W x3A 973911_2012-12-22.PDF\";

I want to create a subs

Answer 1

If you need a SQL solution, this will update the rows:

update yourtable
set field = substr(field, 0, instr(field, ' ')-1) || substr(field, instr(field, '_', instr(field, ' ')))
;

and this will just show the converted value:

select
  yourtable.field,
  case
    when instr(field, '_', instr(field, ' '))>instr(field, ' ')
    then substr(field, 0, instr(field, ' ')-1) || substr(field, instr(field, '_', instr(field, ' ')))
    else field
  end as new_field
from
  yourtable