0 - 2 of 2 tags for Search for first substring in string

I need to remove all the chars from an alpha numeric string ('AL234ps12;') to get 2342 as the result or
fetch 2342 from the an alpha numeric string ('AL234ps12;').
could anyone give me some idea plz.
Thanks & Regards,
Venkatesh Gubba

Hi All,
I have scenario like below:

Requirement - Need to select ID values those are present ( hidden)  in DESCR column. But no joining condition in both the tables.
Query I have used -