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with your_table as (
select '\Google earth\Nest global\ATAP' as TREE from dual union all
select '\Google earth\Nest\Beemoney\' from dual union all
select '\Google\\\BeeKey\' from dual
)
select
TREE,
regexp_replace(
regexp_replace(TREE, '^\\?(.*?)\\?$', '\1'), '\\+', ' > ')
from your_table
| TREE | REGEXP_REPLACE(REGEXP_REPLACE(TREE,'^\?(.*?)\?$','\1'),'\+','>') |
|---|---|
| \Google earth\Nest global\ATAP | Google earth > Nest global > ATAP |
| \Google earth\Nest\Beemoney\ | Google earth > Nest > Beemoney |
| \Google\\BeeKey\ | Google > BeeKey |