What is Flat Hierarchy

Question

Hi, What is Flat Hierarchy Anybody can Explain with Example?

Upendra Pratap Shahi · Answer

http://jpbi.blogspot.in/2007/05/sql-trick-for-flattening-parent-child.html

Deepak Ratan · Answer

Hi Upendra Pratap Shahi According to this link( http://jpbi.blogspot.in/2007/05/sql-trick-for-flattening-parent-child.html ) Can you explain change it into flat format SQL SELECT lev01.node_id id_01, lev01.node_name name_01, lev02.node_id id_02, lev02.node_name name_02, lev03.node_id id_03, lev03.node_name name_03, lev04.node_id id_04, lev04.node_name name_04, lev05.node_id id_05, lev05.node_name name_05, lev06.node_id id_06, lev06.node_name name_06, lev07.node_id id_07, lev07.node_name name_07, lev08.node_id id_08, lev08.node_name name_08, lev09.node_id id_09, lev09.node_name name_09, lev10.node_id id_10, lev10.node_name name_10 FROM hierarchy_parent_child lev01 LEFT OUTER JOIN hierarchy_parent_child lev02 ON lev01.node_id = lev02.parent_id LEFT OUTER JOIN hierarchy_parent_child lev03 ON lev02.node_id = lev03.parent_id LEFT OUTER JOIN hierarchy_parent_child lev04 ON lev03.node_id = lev04.parent_id LEFT OUTER JOIN hierarchy_parent_child lev05 ON lev04.node_id = lev05.parent_id LEFT OUTER JOIN hierarchy_parent_child lev06 ON lev05.node_id = lev06.parent_id LEFT OUTER JOIN hierarchy_parent_child lev07 ON lev06.node_id = lev07.parent_id LEFT OUTER JOIN hierarchy_parent_child lev08 ON lev07.node_id = lev08.parent_id LEFT OUTER JOIN hierarchy_parent_child lev09 ON lev08.node_id = lev09.parent_id LEFT OUTER JOIN hierarchy_parent_child lev10 ON lev09.node_id = lev10.parent_id WHERE lev01.parent_id IS NULL;

What is Flat Hierarchy

Answers (2)