Rails 3 support

Rakefile

@@ -15,7 +15,7 @@ spec = Gem::Specification.new do |s|
   s.add_dependency 'ruby-informix', '>= 0.7.3'
   s.require_path = 'lib'
 
-  s.files = %w(lib/active_record/connection_adapters/informix_adapter.rb)
+  s.files = %w(lib/active_record/connection_adapters/informix_adapter.rb lib/arel/visitors/informix.rb)
 
   s.author = 'Gerardo Santana Gomez Garrido'
   s.email = '[email protected]'

activerecord-informix-adapter.gemspec

@@ -0,0 +1,20 @@
+PKG_NAME = 'activerecord-informix-adapter'
+PKG_VERSION = "1.1.1"
+
+Gem::Specification.new do |s|
+  s.name = PKG_NAME
+  s.summary = 'Informix adapter for Active Record'
+  s.description = 'Active Record adapter for connecting to an IBM Informix database'
+  s.version = PKG_VERSION
+
+  s.add_dependency 'activerecord', '>= 1.15.4.7707'
+  s.add_dependency 'ruby-informix', '>= 0.7.3'
+  s.require_path = 'lib'
+
+  s.files = %w(lib/active_record/connection_adapters/informix_adapter.rb lib/arel/visitors/informix.rb)
+
+  s.author = 'Gerardo Santana Gomez Garrido'
+  s.email = '[email protected]'
+  s.homepage = 'http://rails-informix.rubyforge.org/'
+  s.rubyforge_project = 'rails-informix'
+end

lib/active_record/connection_adapters/informix_adapter.rb

@@ -26,6 +26,7 @@
 # POSSIBILITY OF SUCH DAMAGE.
 
 require 'active_record/connection_adapters/abstract_adapter'
+require 'arel/visitors/informix'
 
 module ActiveRecord
   class Base
@@ -183,6 +184,18 @@ def commit_db_transaction
       def rollback_db_transaction
         @connection.rollback
       end
+
+      def add_limit!(sql, options, scope = :auto)
+        add_limit_offset!(sql, options)
+      end
+
+      def primary_key(table_name) #:nodoc:
+        @connection.cursor(<<-end_sql) do |cur|
+            SELECT FIRST 1 ct.constrname FROM sysconstraints ct, systables st WHERE st.tabid = ct.tabid AND ct.constrtype = 'P' AND st.tabname = '#{table_name}'
+          end_sql
+          cur.open.fetch.first
+        end
+      end
 
       def add_limit_offset!(sql, options)
         if options[:limit]

lib/arel/visitors/informix.rb

@@ -0,0 +1,33 @@
+require 'arel'
+
+module Arel
+  module Visitors
+    class Informix < Arel::Visitors::ToSql
+      def visit_Arel_Nodes_SelectStatement o
+        sql = super(o)
+        if o.limit
+          if o.offset
+            # Modifying the SQL to utilize the skip and limit amounts
+            sql.gsub!(/SELECT/i,"SELECT SKIP #{visit o.offset} LIMIT #{visit o.limit.expr}")
+          else
+            # Modifying the SQL to retrieve only the first #{limit} rows
+            sql = sql.gsub!("SELECT","SELECT FIRST #{visit o.limit.expr}")
+          end
+        # else
+        #   # Modifying the SQL to ensure that no rows will be returned
+        #   sql.gsub!(/SELECT/i,"SELECT * FROM (SELECT")
+        #   sql << ") WHERE 0 = 1"
+        end
+        sql
+      end
+
+      def visit_Arel_Nodes_Limit o 
+      end
+
+      def visit_Arel_Nodes_Offset o
+      end
+    end
+  end
+end
+
+Arel::Visitors::VISITORS['informix'] = Arel::Visitors::Informix