Two conditions in where part of the query out of which 1 is based on length

Question

hi
am having two tables and i need to join them to get my desired output. let me explain with example
table A contains data like
>
col1 col2 col3
12345 sons abcd
23456 snms bcde
34567 snms nil
56478 sons ..
>
table B contains data like
>
col-1 col-2 col-3
sons not-subscribed 0
sons nil-balance 111
snms not-subscribed 0
snms incorrect 111
soai incorrect 111
>
i need the output like
>
col1_of_table_A col3_of_table_A col-2_of_table_B
12345 abcd nilbalance
23456 bcde incorrect
34567 nil not-subscribed
56478 .. not-subscribed
>
likely requirement in sample query format is
select a.col1,a.col3,b.col-2 from A a, B b where ((a.col2=b.col-1 and length(a.col3)>length(b.col-3)) or (a.col2=b.col-1 and length(a.col3)<length(b.col-3)))how to achieve this conditional joint?

Answer 1

Hi,
in your query i just added '..' instead of null for the row starting with 56478 in table A and executed the query as below and it doesn't give my desired output.
with a  as
     select 12345 as col1, 'sons' as col2, 'abcd' as col3 from dual union all
    select 23456, 'snms', 'bcde' from dual union all
    select 34567, 'snms', 'nil' from dual union all
  select 56478, 'sons', '..' from dual
   , b as
     select 'sons' col1, 'not-subscribed' col2, 0 col3 from dual union all
    select 'sons', 'nil-balance', 111 from dual union all
     select 'snms', 'not-subscribed', 0 from dual union all
    select 'snms', 'incorrect', 111 from dual union all
    select 'soai', 'incorrect', 111 from dual
   select  col1, col3, col2
  from
       select a.col1,a.col3,b.col2, row_number() over (partition by a.col1 order by b.col2) rn
        from A a
         left outer join b on (
                              (    a.col2         = b.col1
                               and  length(a.col3) > length(b.col3)
                              or
                               (    a.col2         = b.col1
                               and length(a.col3)  < length(b.col3)
  where rn = 1
  output is
>
COL1     COL3     COL2
12345     abcd     nil-balance
23456     bcde     incorrect
34567     nil     not-subscribed
56478     ..     nil-balance
>
what could be problem?