1 files changed, 30 insertions, 7 deletions
diff --git a/lib/arel/select_manager.rb b/lib/arel/select_manager.rb
index 0fa344945e..7f533fa91b 100644
--- a/lib/arel/select_manager.rb
+++ b/lib/arel/select_manager.rb
@@ -18,10 +18,19 @@ module Arel
       @ctx.wheres
     end
 
+    def offset
+      @ast.offset && @ast.offset.expr
+    end
+
     def skip amount
-      @ast.offset = Nodes::Offset.new(amount)
+      if amount
+        @ast.offset = Nodes::Offset.new(amount)
+      else
+        @ast.offset = nil
+      end
       self
     end
+    alias :offset= :skip
 
     ###
     # Produces an Arel::Nodes::Exists node
@@ -37,10 +46,16 @@ module Arel
       @ctx.wheres.map { |c| to_sql.accept c }
     end
 
-    def lock locking = true
-      # FIXME: do we even need to store this?  If locking is +false+ shouldn't
-      # we just remove the node from the AST?
-      @ast.lock = Nodes::Lock.new
+    def lock locking = Arel.sql('FOR UPDATE')
+      case locking
+      when true
+        locking = Arel.sql('FOR UPDATE')
+      when Arel::Nodes::SqlLiteral
+      when String
+        locking = Arel.sql locking
+      end
+
+      @ast.lock = Nodes::Lock.new(locking)
       self
     end
 
@@ -161,13 +176,21 @@ module Arel
         node_class = Nodes::With
       end
       @ast.with = node_class.new(subqueries.flatten)
+
+      self
     end
 
     def take limit
-      @ast.limit = Nodes::Limit.new(limit)
-      @ctx.top   = Nodes::Top.new(limit)
+      if limit
+        @ast.limit = Nodes::Limit.new(limit)
+        @ctx.top   = Nodes::Top.new(limit)
+      else
+        @ast.limit = nil
+        @ctx.top   = nil
+      end
       self
     end
+    alias limit= take
 
     def join_sql
       return nil if @ctx.source.right.empty?