Modified: trunk/activerecord-jdbc/lib/jdbc_adapter/jdbc_oracle.rb (743 => 744)
--- trunk/activerecord-jdbc/lib/jdbc_adapter/jdbc_oracle.rb 2007-09-25 07:40:30 UTC (rev 743)
+++ trunk/activerecord-jdbc/lib/jdbc_adapter/jdbc_oracle.rb 2007-09-25 15:19:21 UTC (rev 744)
@@ -34,7 +34,18 @@
end
def self.adapter_selector
- [/oracle/i, lambda {|cfg,adapt| adapt.extend(::JdbcSpec::Oracle)}]
+ [/oracle/i, lambda {|cfg,adapt| adapt.extend(::JdbcSpec::Oracle)
+=begin
+ (adapt.methods - %w(send __send__ id class methods is_a? kind_of? verify! active?)).each do |name|
+ new_name = "__#{name}"
+ (class << adapt; self; end).send :alias_method, new_name, name
+ (class << adapt; self; end).send :define_method, name do |*args|
+ puts "#{name}(#{args.inspect})"
+ adapt.send new_name, *args
+ end
+ end
+=end
+ }]
end
module Column
@@ -90,6 +101,10 @@
end
end
+ def table_alias_length
+ 30
+ end
+
def default_sequence_name(table, column) #:nodoc:
"#{table}_seq"
end
@@ -132,8 +147,8 @@
end
def _execute(sql, name = nil)
- case sql.strip
- when /^(select|show)/i:
+ case sql.strip
+ when /\A\(?\s*(select|show)/i:
@connection.execute_query(sql)
else
@connection.execute_update(sql)
@@ -230,6 +245,43 @@
end
end
+ # SELECT DISTINCT clause for a given set of columns and a given ORDER BY clause.
+ #
+ # Oracle requires the ORDER BY columns to be in the SELECT list for DISTINCT
+ # queries. However, with those columns included in the SELECT DISTINCT list, you
+ # won't actually get a distinct list of the column you want (presuming the column
+ # has duplicates with multiple values for the ordered-by columns. So we use the
+ # FIRST_VALUE function to get a single (first) value for each column, effectively
+ # making every row the same.
+ #
+ # distinct("posts.id", "posts.created_at desc")
+ def distinct(columns, order_by)
+ return "DISTINCT #{columns}" if order_by.blank?
+
+ # 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 = 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
+
+
# QUOTING ==================================================
#
# see: abstract/quoting.rb
@@ -268,12 +320,10 @@
end
private
-
- def select(sql, name = nil)
- records = execute(sql, name)
- records.map do |col|
+ def select(sql, name=nil)
+ records = execute(sql,name)
+ records.each do |col|
col.delete('raw_rnum_')
- col
end
records
end
