[Oracle] Split on query

Question

Hi,

I have in my DB a column 'note', where the content should be:
"Buongiorno a tutti||Che splendida giornata"

I would write a query for extract two string:
- string1 = "Buongiorno a tutti"
- string2 = "che splendida giornata"
if the first part or second part of string is empty I return null..

My special char is the double pipe "||".

How can I implement it?

Thanks.