Outer Join Two tables

Question

I got two Tables.APPROVAL_ROUTING_TAB and doc_issue_tab where APPROVAL_ROUTING_TAB has more rows. I need to do the join two tables such that All the rows in APPROVAL_ROUTING_TAB should be displayed ( more rows) but still connect with the doc_issue_tab. I did an outer join syntax failed.
What is the correct syntax for this.
Key_ref takes the following pattern "DOC_CLASS=PR_CLASS_1^DOC_NO=1000007^DOC_REV=A3^DOC_SHEET=1^"
SELECT
ar.line_no LINE_NO,
ar.step_no STEP_NO,
ar.lu_name LU_NAME,
ar.key_ref KEY_REF,
ar.description DESCRIPTION,
di.status STATUS
FROM APPROVAL_ROUTING_TAB ar, doc_issue_tab di
WHERE
ar.key_ref = 'DOC_CLASS='||di.doc_class||'^DOC_NO='||di.doc_no||'^DOC_REV='||di.doc_rev||'^DOC_SHEET='||di.doc_sheet||'^') (+)
Thansk in advance
Prash

Answer 1

Other options include:
with t1 as (select 1 id, 'd1=fred^d2=john^d3=bob^' col2 from dual union all
            select 1 id, 'd1=fred^d2=john^d3=george' col2 from dual),
     t2 as (select 'fred' d1, 'john' d2, 'bob' d3 from dual union all
            select 'jim' d1, 'john' d2, 'bob' d3 from dual)
select *
from   t1, (select t2.*, 'd1='||d1||'^d2='||d2||'^d3='||d3||'^' full_col
            from t2) t3
where  t1.col2 = t3.full_col (+);
        ID COL2                      D1   D2   D3  FULL_COL              
         1 d1=fred^d2=john^d3=bob^   fred john bob d1=fred^d2=john^d3=bob^
         1 d1=fred^d2=john^d3=george                                     
with t1 as (select 1 id, 'd1=fred^d2=john^d3=bob^' col2 from dual union all
            select 1 id, 'd1=fred^d2=john^d3=george' col2 from dual),
     t2 as (select 'fred' d1, 'john' d2, 'bob' d3 from dual union all
            select 'jim' d1, 'john' d2, 'bob' d3 from dual)
select *
from   t1 left outer join t2 on (t1.col2 = 'd1='||d1||'^d2='||d2||'^d3='||d3||'^');
        ID COL2                      D1   D2   D3
         1 d1=fred^d2=john^d3=bob^   fred john bob
         1 d1=fred^d2=john^d3=george