1 files changed, 50 insertions, 0 deletions
diff --git a/lib/arel/engines/sql/relations/relation.rb b/lib/arel/engines/sql/relations/relation.rb
new file mode 100644
index 0000000000..4cfb83a601
--- /dev/null
+++ b/lib/arel/engines/sql/relations/relation.rb
@@ -0,0 +1,50 @@
+module Arel
+  class Relation
+    def to_sql(formatter = Sql::SelectStatement.new(self))
+      formatter.select select_sql, self
+    end
+
+    def select_sql
+      build_query \
+        "SELECT     #{select_clauses.join(', ')}",
+        "FROM       #{table_sql(Sql::TableReference.new(self))}",
+        (joins(self)                                   unless joins(self).blank? ),
+        ("WHERE     #{where_clauses.join("\n\tAND ")}" unless wheres.blank?      ),
+        ("GROUP BY  #{group_clauses.join(', ')}"       unless groupings.blank?   ),
+        ("ORDER BY  #{order_clauses.join(', ')}"       unless orders.blank?      ),
+        ("LIMIT     #{taken}"                          unless taken.blank?       ),
+        ("OFFSET    #{skipped}"                        unless skipped.blank?     )
+    end
+
+    def inclusion_predicate_sql
+      "IN"
+    end
+
+    def christener
+      @christener ||= Sql::Christener.new
+    end
+
+  protected
+
+    def build_query(*parts)
+      parts.compact.join("\n")
+    end
+
+    def select_clauses
+      attributes.collect { |a| a.to_sql(Sql::SelectClause.new(self)) }
+    end
+
+    def where_clauses
+      wheres.collect { |w| w.to_sql(Sql::WhereClause.new(self)) }
+    end
+
+    def group_clauses
+      groupings.collect { |g| g.to_sql(Sql::GroupClause.new(self)) }
+    end
+
+    def order_clauses
+      orders.collect { |o| o.to_sql(Sql::OrderClause.new(self)) }
+    end
+
+  end
+end