diff options
Diffstat (limited to 'activerecord')
| -rw-r--r-- | activerecord/CHANGELOG | 2 | ||||
| -rw-r--r-- | activerecord/lib/active_record/connection_adapters/oracle_adapter.rb | 27 |
2 files changed, 18 insertions, 11 deletions
diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG index d94ae721e7..5fa13915fb 100644 --- a/activerecord/CHANGELOG +++ b/activerecord/CHANGELOG @@ -6,7 +6,7 @@ * acts_as_nested_set works with single-table inheritance. #6030 [Josh Susser] -* PostgreSQL: use a subselect to correctly perform eager finds with :limit and :order. #4668 [eventualbuddha] +* PostgreSQL, Oracle: correctly perform eager finds with :limit and :order. #4668, #7021 [eventualbuddha, Michael Schoen] * Pass a range in :conditions to use the SQL BETWEEN operator. #6974 [dcmanges] Student.find(:all, :conditions => { :grade => 9..12 }) diff --git a/activerecord/lib/active_record/connection_adapters/oracle_adapter.rb b/activerecord/lib/active_record/connection_adapters/oracle_adapter.rb index def2a69256..53cf2a439a 100644 --- a/activerecord/lib/active_record/connection_adapters/oracle_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/oracle_adapter.rb @@ -459,22 +459,29 @@ begin def distinct(columns, order_by) return "DISTINCT #{columns}" if order_by.blank? - # construct a clean list of column names from the ORDER BY clause, removing - # any asc/desc modifiers - order_columns = order_by.split(',').collect! { |s| s.split.first } - order_columns.delete_if &:blank? - - # simplify the ORDER BY to just use positional syntax, to avoid the complexity of - # having to create valid column aliases for the FIRST_VALUE columns - order_by.replace(((offset=columns.count(',')+2) .. offset+order_by.count(',')).to_a * ", ") - # construct a valid DISTINCT clause, ie. one that includes the ORDER BY columns, using # FIRST_VALUE such that the inclusion of these columns doesn't invalidate the DISTINCT - order_columns.map! { |c| "FIRST_VALUE(#{c}) OVER (PARTITION BY #{columns} ORDER BY #{c})" } + order_columns = order_by.split(',').map { |s| s.strip }.reject(&:blank?) + order_columns = order_columns.zip((0...order_columns.size).to_a).map do |c, i| + "FIRST_VALUE(#{c.split.first}) OVER (PARTITION BY #{columns} ORDER BY #{c}) AS alias_#{i}__" + end sql = "DISTINCT #{columns}, " sql << order_columns * ", " end + # ORDER BY clause for the passed order option. + # + # Uses column aliases as defined by #distinct. + def add_order_by_for_association_limiting!(sql, options) + return sql if options[:order].blank? + + order = options[:order].split(',').collect { |s| s.strip }.reject(&:blank?) + order.map! {|s| $1 if s =~ / (.*)/} + order = order.zip((0...order.size).to_a).map { |s,i| "alias_#{i}__ #{s}" }.join(', ') + + sql << "ORDER BY #{order}" + end + private def select(sql, name = nil) |