Need a way to extract substring from string in oracle

Question

Hi all,
I have one requirement related to extracting string from a paramater.
suppose the string may like this in various format
string:= 'This my string <Rid//problem/123456>'
or
string:= '<Rid//problem/123456> This my string'
or
string:= ' This is <Rid//problem/123456> my string'
Now my requirement is i need to extract 123456 using pl/sql block.
is there any way in oracle to get this thing done.
Thanks n regards
Laxman

Answer 1

Hi,
What version of Oracle ?
How do you delimit the string to extract ?
- always between the last / and before the >
- the last string mande of number ?
- the first string made of number ?
Here are 3 possible answers :SQL> with s as (
  2  select 'This my string <Rid//problem/123456>' s from dual
  3  union all select '<Rid//problem/123456> This my string' from dual
  4  union all select ' This is <Rid//problem/123456> my string' from dual
  5  )
  6  select s.s,
  7  regexp_replace(s,'^.*/([0-9]*).*$','\1') r1,
  8  regexp_replace(s,'^[^0-9]*(.*?)[^0-9]*$','\1') r2,
  9  regexp_replace(s,'^.*/(.*?)>.*$','\1') r3
10  from s ;
S                                        R1       R2       R3
This my string <Rid//problem/123456>     123456   123456   123456
<Rid//problem/123456> This my string     123456   123456   123456
This is <Rid//problem/123456> my string 123456   123456   123456If you're on 10g or more...
Of course it also works in PL/SQL :SQL> l
  1  declare
  2  r1 varchar2(50) := 'This my string <Rid//problem/123456>';
  3  r2 varchar2(50) := '<Rid//problem/123456> This my string';
  4  r3 varchar2(50) := ' This is <Rid//problem/123456> my string';
  5  r1b varchar2(50);
  6  r2b varchar2(50);
  7  r3b varchar2(50);
  8  begin
  9  r1b := regexp_replace(r1,'^.*/([0-9]*).*$','\1') ;
10  r2b := regexp_replace(r2,'^[^0-9]*(.*?)[^0-9]*$','\1') ;
11  r3b := regexp_replace(r3,'^.*/(.*?)>.*$','\1') ;
12  dbms_output.put_line('1 : '||r1||' -> '||r1b);
13  dbms_output.put_line('2 : '||r2||' -> '||r2b);
14  dbms_output.put_line('3 : '||r3||' -> '||r3b);
15* end;
SQL> /
1 : This my string <Rid//problem/123456> -> 123456
2 : <Rid//problem/123456> This my string -> 123456
3 :  This is <Rid//problem/123456> my string -> 123456
PL/SQL procedure successfully completed.Edited by: Nicosa on Jul 23, 2010 3:22 PM