Module: ClosureTree::NumericDeterministicOrdering::ClassMethods

Defined in:
lib/closure_tree/numeric_deterministic_ordering.rb

Instance Method Summary collapse

Instance Method Details

#_ct_sum_order_by(node = nil) ⇒ Object

If node is nil, order the whole tree.



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# File 'lib/closure_tree/numeric_deterministic_ordering.rb', line 53

def _ct_sum_order_by(node = nil)
  stats_sql = "    SELECT\n      count(*) as total_descendants,\n      max(generations) as max_depth\n    FROM \#{_ct.quoted_hierarchy_table_name}\n  SQL\n  stats_sql += \" WHERE ancestor_id = \#{_ct.quote(node.id)}\" if node\n  h = _ct.connection.select_one(stats_sql)\n\n  depth_column = node ? 'depths.generations' : 'depths.max_depth'\n\n  node_score = \"(1 + anc.\#{_ct.quoted_order_column(false)}) * \" +\n    \"power(\#{h['total_descendants']}, \#{h['max_depth'].to_i + 1} - \#{depth_column})\"\n\n  # We want the NULLs to be first in case we are not ordering roots and they have NULL order.\n  Arel.sql(\"SUM(\#{node_score}) IS NULL DESC, SUM(\#{node_score})\")\nend\n".squish

#roots_and_descendants_preordered ⇒ Object 



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# File 'lib/closure_tree/numeric_deterministic_ordering.rb', line 72

def roots_and_descendants_preordered
  if _ct.dont_order_roots
    raise ClosureTree::RootOrderingDisabledError.new("Root ordering is disabled on this model")
  end

  join_sql = "    JOIN \#{_ct.quoted_hierarchy_table_name} anc_hier\n      ON anc_hier.descendant_id = \#{_ct.quoted_table_name}.\#{_ct.quoted_id_column_name}\n    JOIN \#{_ct.quoted_table_name} anc\n      ON anc.\#{_ct.quoted_id_column_name} = anc_hier.ancestor_id\n    JOIN (\n      SELECT descendant_id, max(generations) AS max_depth\n      FROM \#{_ct.quoted_hierarchy_table_name}\n      GROUP BY descendant_id\n    ) \#{ _ct.t_alias_keyword } depths ON depths.descendant_id = anc.\#{_ct.quoted_id_column_name}\n  SQL\n  joins(join_sql)\n    .group(\"\#{_ct.quoted_table_name}.\#{_ct.quoted_id_column_name}\")\n    .reorder(_ct_sum_order_by)\nend\n".squish