returning nil for tables that do not exist

1 files changed, 16 insertions, 0 deletions

diff --git a/lib/arel/table.rb b/lib/arel/table.rb
index 06bbe7b99e..d23245691b 100644
--- a/lib/arel/table.rb
+++ b/lib/arel/table.rb
@@ -88,8 +88,24 @@ module Arel
     end
 
     def [] name
+      return nil unless table_exists?
+
       name = name.to_sym
       columns.find { |column| column.name == name }
     end
+
+    private
+    def table_exists?
+      @table_exists ||= tables.key?(@name) || engine.connection.table_exists?(name)
+    end
+
+    def tables
+      self.class.table_cache(@engine)
+    end
+
+    @@table_cache = nil
+    def self.table_cache engine # :nodoc:
+      @@table_cache ||= Hash[engine.connection.tables.map { |x| [x,true] }]
+    end
   end
 end