Replace substr, instr with Reg_exp, is this possible,

Question

Hi Team,
I have Small requirement below, i have writen Query For this but was thinking Is there Any better way Of
doing it, esp With Use To reg_exp,
i have Some code As shown below
'23456_TR_ABC_CODE12_JPM-(1)100-(1)150'
From this code i Only want portion which Is Between 'TR_' And '_CODE12' i.e. ABC,
given Is my Query And its output
Select
substr( substr('23456_TR_ABC_CODE12_JPM-(1)100-(1)150',instr('23456_TR_ABC_CODE12_JPM-(1)100-(1)150','TR_',1,1)+3),
        1,
        instr(
              substr('23456_TR_ABC_CODE12_JPM-(1)100-(1)150',instr('23456_TR_ABC_CODE12_JPM-(1)100-(1)150','TR_',1,1)+3),
              '_',1,1
              -1) "word"
From dual;
        word
1     ABC
kindly let me know If there Is Any better way Of doing it,,,

Answer 1

Jeneesh, in case there are several TR_ or _CODE12 in the line I'd advice to use non-greedy operators.
SQL> with t as
  2     (select '23456_TR_ABC_CODE12_JPM_(1)_100_CODE12_ASJ' word from dual)
  3     select regexp_replace(word, '.*TR_<font color="red">(.*)</font>_CODE12.*', '\1') word
  4       from t;
WORD
<font color="red">ABC_CODE12_JPM_(1)_100</font>
SQL>
It is working with (+) sign.
SQL> with t as
  2     (select '23456_TR_ABC_CODE12_JPM_(1)_100_CODE12_ASJ' word from dual)
  3     select regexp_replace(word, '.*TR_<font color="blue">(.+?)</font>_CODE12.*', '\1') word
  4       from t;
WORD
<font color="blue">ABC</font>
SQL>
But I don't understand why it is not working with (*) sign :((
SQL> with t as
  2     (select '23456_TR_ABC_CODE12_JPM_(1)_100_CODE12_ASJ' word from dual)
  3     select regexp_replace(word, '.*TR_<font color="green">(.*?)</font>_CODE12.*', '\1') word
  4       from t;
WORD
<font color="green">ABC_CODE12_JPM_(1)_100</font>Maybe someone can explain?
Several more examples:
the first and the last of them are really strange, at least for me:
SQL> with t as
  2     (select '23456_TR_ABC_CODE12_JPM_(1)_100_CODE12_ASJ' word from dual)
  3     select regexp_replace(word, '^<font color="red">.*</font>TR_<font color="red">(.*?)</font>_CODE12.*$', '\1') word
  4       from t;
WORD
<font color="red">ABC_CODE12_JPM_(1)_100</font>
SQL>
SQL> with t as
  2     (select '23456_TR_ABC_CODE12_JPM_(1)_100_CODE12_ASJ' word from dual)
  3     select regexp_replace(word, '^<font color="blue">.*?</font>TR_<font color="blue">(.*?)</font>_CODE12.*$', '\1') word
  4       from t;
WORD
<font color="blue">ABC</font>
SQL>
SQL> with t as
  2     (select '23456_TR_ABC_CODE12_JPM_(1)_100_CODE12_ASJ' word from dual)
  3     select regexp_replace(word, '^<font color="red">.*?</font>TR_<font color="red">(.*)</font>_CODE12.*$', '\1') word
  4       from t;
WORD
<font color="red">ABC</font>
SQL>