1 files changed, 72 insertions, 4 deletions
diff --git a/lib/arel/engines/sql/relations/compiler.rb b/lib/arel/engines/sql/relations/compiler.rb
index 597ed88683..fc8d484276 100644
--- a/lib/arel/engines/sql/relations/compiler.rb
+++ b/lib/arel/engines/sql/relations/compiler.rb
@@ -21,20 +21,55 @@ module Arel
           ("#{locked}"                                   unless locked.blank?)
       end
 
-      def limited_update_conditions(conditions, taken)
-        conditions << " LIMIT #{taken}"
-        quoted_primary_key = engine.quote_table_name(primary_key)
-        "WHERE #{quoted_primary_key} IN (SELECT #{quoted_primary_key} FROM #{engine.connection.quote_table_name table.name} #{conditions})"
+      def delete_sql
+        build_query \
+          "DELETE",
+          "FROM #{table_sql}",
+          ("WHERE #{wheres.collect(&:to_sql).join(' AND ')}" unless wheres.blank? ),
+          (add_limit_on_delete(taken)                        unless taken.blank?  )
       end
 
       def add_limit_on_delete(taken)
         "LIMIT #{taken}"
       end
 
+      def insert_sql(include_returning = true)
+        insertion_attributes_values_sql = if record.is_a?(Value)
+          record.value
+        else
+          attributes = record.keys.sort_by do |attribute|
+            attribute.name.to_s
+          end
+
+          first = attributes.collect do |key|
+            engine.quote_column_name(key.name)
+          end.join(', ')
+
+          second = attributes.collect do |key|
+            key.format(record[key])
+          end.join(', ')
+
+          build_query "(#{first})", "VALUES (#{second})"
+        end
+
+        build_query \
+          "INSERT",
+          "INTO #{table_sql}",
+          insertion_attributes_values_sql,
+          ("RETURNING #{engine.quote_column_name(primary_key)}" if include_returning && compiler.supports_insert_with_returning?)
+      end
+
       def supports_insert_with_returning?
         false
       end
 
+      def update_sql
+        build_query \
+          "UPDATE #{table_sql} SET",
+          assignment_sql,
+          build_update_conditions_sql
+      end
+
     protected
       def method_missing(method, *args, &block)
         relation.send(method, *args, &block)
@@ -44,6 +79,39 @@ module Arel
         parts.compact.join(" ")
       end
 
+      def assignment_sql
+        if assignments.respond_to?(:collect)
+          attributes = assignments.keys.sort_by do |attribute|
+            attribute.name.to_s
+          end
+
+          attributes.map do |attribute|
+            value = assignments[attribute]
+            "#{engine.quote_column_name(attribute.name)} = #{attribute.format(value)}"
+          end.join(", ")
+        else
+          assignments.value
+        end
+      end
+
+      def build_update_conditions_sql
+        conditions = ""
+        conditions << " WHERE #{wheres.collect(&:to_sql).join(' AND ')}" unless wheres.blank?
+        conditions << " ORDER BY #{order_clauses.join(', ')}" unless orders.blank?
+
+        unless taken.blank?
+          conditions = limited_update_conditions(conditions, taken)
+        end
+
+        conditions
+      end
+
+      def limited_update_conditions(conditions, taken)
+        conditions << " LIMIT #{taken}"
+        quoted_primary_key = engine.quote_column_name(primary_key)
+        "WHERE #{quoted_primary_key} IN (SELECT #{quoted_primary_key} FROM #{engine.connection.quote_table_name table.name} #{conditions})"
+      end
+
     end
 
   end