I am using oracle 12c database to store data,and .net asp c# to create a web application. i am new with oracle and know about the new feature of identity columns.

I want to generate a number xx-y-zzz such that xx is the current financial year,y is a integer belongs to (1-9) and zzz is a value that starts with 001 and is incremented whenever a button is clicked.

and also

->zzz is a number that depends on y, eg. 14-1-001 and 14-2-001 can both exist simultaneously ->if the current financial year changes then the value zzz will start from 001

thanks