Hierarchical sql

Question

hello,
I am seeking help with a hierarchical query.
My table has five columns:
grade (number)
score (number)
name (varchar)
record_id (number)
parentid (number)
A parentid is a record_id at a higher level in the hierarchy.
Grade and Score are used to order (sort) each level of the hierarchy.
The data looks like this:
grade - score - name - record_id - parentid
1 - 1 - name1 - 101 - 0
1 - 2 - name2 - 102 - 0
1 - 3 - name3 - 103 - 0
2 - 1 - name4 - 104 - 101
2 - 2 - name5 - 105 - 101
2 - 1 - name6 - 106 - 102
2 - 2 - name7 - 107 - 102
2 - 1 - name8 - 108 - 103
2 - 2 - name9 - 109 - 103
I would like the query to display the data in the following sequence:
grade - score - name - record_id - parentid
1 - 1 - name1 - 101 - 0
2 - 1 - name4 - 104 - 101
2 - 2 - name5 - 105 - 101
1 - 1 - name2 - 102 - 0
2 - 1 - name6 - 106 - 102
2 - 2 - name7 - 107 - 102
1 - 1 - name3 - 103 - 0
2 - 1 - name8 - 108 - 103
2 - 2 - name9 - 109 - 103
The simplest query to get this resultset sequence is adequate. No need for padding or other features.
Thank you.

Answer 1

All columns in your sample have same order so it isn't possible to tell by what column you want to order siblings. I'll assume by name:
select  *
  from  your_table
  start with parentid = 0
  connect by parentid = prior record_id
  order siblings by name
/For example:
with sample_table as (
                      select 1 grade,1 score,'name1' name,101 record_id,0 parentid from dual union all
                      select 1,2,'name2',102,0 from dual union all
                      select 1,3,'name3',103,0 from dual union all
                      select 2,1,'name4',104,101 from dual union all
                      select 2,2,'name5',105,101 from dual union all
                      select 2,1,'name6',106,102 from dual union all
                      select 2,2,'name7',107,102 from dual union all
                      select 2,1,'name8',108,103 from dual union all
                      select 2,2,'name9',109,103 from dual
select  *
  from  sample_table
  start with parentid = 0
  connect by parentid = prior record_id
  order siblings by name
     GRADE      SCORE NAME   RECORD_ID   PARENTID
         1          1 name1        101          0
         2          1 name4        104        101
         2          2 name5        105        101
         1          2 name2        102          0
         2          1 name6        106        102
         2          2 name7        107        102
         1          3 name3        103          0
         2          1 name8        108        103
         2          2 name9        109        103
9 rows selected.
SQL> SY.