Return Only number from a string if it contains numbers

Question

For example,
string is abc123CD need to find out a method to read only numbers in the string
i.e.

  select a_postgres_function(\'a         


        

Answer 1

Try this:

select (regexp_matches('abc123CD', '\d+'))[1];

Since regexp_matches returns array of text, you should access the first element by [1].