Oracle's recursive operations (tree operations) infinite tree shape

Recursive operation of Oracle (tree operation) Start with org_id = ' 1 ' Connect by prior parent_id=son_id

 1. Preface    Oracle's recursive operation, in our web page directory structure will be used frequently, is said to be the interview often out of the topic, and some things on the internet is not very clear, so I tidied up a bit, the following mainly through an example to illustrate, You can run it directly from the copy code.    www.2cto.com  2.start with org_id = ' condition 1 '  prior parent_id =  son_id; The role of    this is to find out all the tree structure, the tree directory is placed in the same table, such as  1 |--2 |--3 |--4    |--5        |--6 |--7    |--8       |--9          |--10   www.2cto.com   How this structure can be found, this particular query, connect by Perior comes in handy.  3. Code  java Code  create table testtemp   (   parent_id    VARCHAR2 (+),     son_id VARCHAR2 (+)  );    insert into testtemp values (' 1 ', ' 0 ');  insert into testtemp values (' 1 ', ' 2 ');  insert into testtemp values (' 1 ', ' 3 ');  insert into testtemp values (' 1 ', ' 4 ');  insert into testtemp values (' 1 ', ' 7 ');  insert into testtemp values (' 4 ', ' 5 ');  insert into Testtemp VAlues (' 5 ', ' 6 ');  insert into testtemp values (' 7 ', ' 8 ');  insert into testtemp values (' 8 ', ' 9 ');  insert into testtemp values (' 9 ', ' 10 ');  commit;  select * from Testtemp   start with parent_id= ' 1 '  connect  by  parent_id= prior Son_ID &NB sp;   www.2cto.com   Results:  1012131445561778899Ten4. Summing up the example above, the function is to implement traversing all nodes. If Prior is behind connect by, it's the search from the top

Oracle's recursive operations (tree operations) infinite tree shape