Count occurrences of matched words

Question

All,
Does anyone know the syntax or algorithm to count the occurrences of matched words that where compared from two separate columns or tables? Below is a simple example of the type of comparison I would like to perform. I found the function regexp_count, but it only works in 11g. Unfortunately, I have Oracle 10g. Any help would be greatly appreciated. Thanks
i.e.
drop table compare_matched_words;
create table compare_matched_words (
query_id number,
query_string1 varchar2(80),
query_string2 varchar2(80)
insert into compare_matched_words values (1, 'oracle 255','oracle1 255');
insert into compare_matched_words values (2, 'larry or ellison','larry or');
insert into compare_matched_words values (3, 'oracle and text','and');
insert into compare_matched_words values (4, 'market1 share','market share');
insert into compare_matched_words values (5, 'larry or',' larry or ellison');
insert into compare_matched_words values (6, 'oracle1 255','oracle 255');

Answer 1

Issue is not in 11g. Before you can solve the task you need to split QUERY_STRING1 and QUERY_STRING2 into words and then compare words for same QUERY_ID. To split string into words use something like:
select  query_id,
        regexp_substr(query_string1,'\w+',1,column_value) query_string1_word
  from  compare_matched_words t,
        table(
              cast(
                   multiset(
                            select  level
                              from  dual
                              connect by level <= length(regexp_replace(regexp_replace(QUERY_STRING1,'\w+','A'),'[^A]'))
                           ) as sys.OdciNumberList
SQL> /
           QUERY_ID QUERY_STRING1_WORD
                  1 oracle
                  1 255
                  2 larry
                  2 or
                  2 ellison
                  3 oracle
                  3 and
                  3 text
                  4 market1
                  4 share
                  5 larry
           QUERY_ID QUERY_STRING1_WORD
                  5 or
                  6 oracle1
                  6 255
14 rows selected.
SQL> Now:
select  t1.query_id,
        t1.query_string1,
        t2.query_string2,
        count(*) matchin_word_count
  from  (
         select  query_id,
                 query_string1,
                 regexp_substr(query_string1,'\w+',1,column_value) query_string1_word
           from  compare_matched_words t,
                 table(
                       cast(
                            multiset(
                                     select  level
                                        from  dual
                                       connect by level <= length(regexp_replace(regexp_replace(query_string1,'\w+','A'),'[^A]'))
                                    ) as sys.OdciNumberList
        ) t1,
         select  query_id,
                 query_string2,
                 regexp_substr(query_string2,'\w+',1,column_value) query_string2_word
           from  compare_matched_words t,
                 table(
                       cast(
                            multiset(
                                     select  level
                                        from  dual
                                       connect by level <= length(regexp_replace(regexp_replace(query_string2,'\w+','A'),'[^A]'))
                                    ) as sys.OdciNumberList
        ) t2
  where t2.query_id = t1.query_id
    and t2.query_string2_word = t1.query_string1_word
  group by t1.query_id,
           t1.query_string1,
           t2.query_string2
  order by t1.query_id
           QUERY_ID QUERY_STRING1                  QUERY_STRING2                   MATCHIN_WORD_COUNT
                  1 oracle 255                     oracle1 255                                      1
                  2 larry or ellison               larry or                                         2
                  3 oracle and text                and                                              1
                  4 market1 share                  market share                                     1
                  5 larry or                        larry or ellison                                2
                  6 oracle1 255                    oracle 255                                       1
6 rows selected.
SQL> SY.