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stringoracle-databasecsvoracle11gtokenize

listunagg function?


is there such thing in oracle like listunagg function? For example, if I have a data like:

user_id degree_fi degree_en degree_sv
3601464 3700 1600 2200
1020 100 0 0
3600520 100,3200,400 1300, 800, 3000 1400, 600, 1500
3600882 0 100 200

and I'd like to show data like this:

user_id degree_fi degree_en degree_sv
3601464 3700 1600 2200
1020 100 0 0
3600520 100 1300 1400
3600882 0 100 200
3600520 3200 800 600
3600520 400 3000 1500

I tried to find some function like opposite of listagg but couldn't find any.


Solution

  • As @be here now has already noted in the comment Oracle doesn't provide such a function. So as a quick workaround you could write similar query:

    with t1(user_id, degree_fi, degree_en, degree_sv) as
    (
      select 3601464, '3700', '1600', '2200' from dual union all
      select 1020   , '100' , '0'   , '0'    from dual union all
      select 3600520, '100,3200,400', '1300, 800, 3000', '1400, 600, 1500'  from dual union all
      select 3600882, '0',    '100',  '200'  from dual
    ),
    Occurence(ocr) as(
      select Level as ocr
        from (select max(greatest(regexp_count(degree_fi, '[^,]+')
                                 , regexp_count(degree_en, '[^,]+')
                                 , regexp_count(degree_sv, '[^,]+')
                                 )
                        ) mx
                from t1    
              ) 
        connect by level <= mx
    )
    select *
      from (
    select User_id
         , regexp_substr(degree_fi, '[^,]+', 1, o.ocr) as degree_fi
         , regexp_substr(degree_en, '[^,]+', 1, o.ocr) as degree_en
         , regexp_substr(degree_sv, '[^,]+', 1, o.ocr) as degree_sv
       from t1 t
      cross join Occurence o
    )
    where degree_fi is not null
      or degree_en is not null 
      or degree_sv is not null
    

    Result:

    User_Id   Degree_Fi  Degree_En  Degree_Sv
    ------------------------------------------------------------ 
    3601464   3700       1600       2200 
    1020      100        0          0 
    3600520   100        1300       1400 
    3600882   0          100        200 
    3600520   3200       800        600 
    3600520   400        3000       1500