只取字符串中的数字

--只取字符串中的数字，by gisoracle function getnumber(str varchar2) return varchar2 is rstr varchar2(4000); begin if str is null then return null; else rstr := ''; for i IN 1 .. length(str) loop if (ascii(substr(str, i, 1)) between 48 and 57) or (substr(str, i, 1) = '.') then rstr := rstr || substr(str, i, 1); end if; end loop; return rstr; end if; end;