primary key support for sqlserver adapter

gistfile1.diff

diff --git a/lib/active_record/connection_adapters/sqlserver/schema_statements.rb b/lib/active_record/connection_adapters/sqlserver/schema_statements.rb
index 2e490a1..b2b6a87 100644
--- a/lib/active_record/connection_adapters/sqlserver/schema_statements.rb
+++ b/lib/active_record/connection_adapters/sqlserver/schema_statements.rb
@@ -193,10 +193,13 @@ module ActiveRecord
               ELSE NULL
             END AS [is_nullable],
             CASE 
-              WHEN CCU.COLUMN_NAME IS NOT NULL AND TC.CONSTRAINT_TYPE = N'PRIMARY KEY' THEN 1
               WHEN COLUMNPROPERTY(OBJECT_ID(columns.TABLE_SCHEMA+'.'+columns.TABLE_NAME), columns.COLUMN_NAME, 'IsIdentity') = 1 THEN 1
               ELSE NULL
-            END AS [is_identity]
+            END AS [is_identity],
+            CASE
+              WHEN CCU.COLUMN_NAME IS NOT NULL AND TC.CONSTRAINT_TYPE = N'PRIMARY KEY' THEN 1
+              ELSE NULL
+            END AS [is_primary_key]
             FROM #{db_name_with_period}INFORMATION_SCHEMA.COLUMNS columns
             LEFT OUTER JOIN #{db_name_with_period}INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS TC ON TC.TABLE_NAME = columns.TABLE_NAME AND TC.CONSTRAINT_TYPE = N'PRIMARY KEY' 
             LEFT OUTER JOIN #{db_name_with_period}INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE AS CCU ON TC.CONSTRAINT_NAME = CCU.CONSTRAINT_NAME AND CCU.COLUMN_NAME = columns.COLUMN_NAME
@@ -240,6 +243,7 @@ module ActiveRecord
                                  end
             ci[:null] = ci[:is_nullable].to_i == 1 ; ci.delete(:is_nullable)
             ci[:is_identity] = ci[:is_identity].to_i == 1
+            ci[:is_primary_key] = ci[:is_primary_key].to_i == 1
             ci
           end
         end
@@ -389,7 +393,7 @@ module ActiveRecord
         end
 
         def identity_column(table_name)
-          columns(table_name).detect(&:primary) || columns(table_name).detect(&:is_identity?)
+          columns(table_name).detect(&:is_identity?)
         end
 
       end
diff --git a/lib/active_record/connection_adapters/sqlserver/version.rb b/lib/active_record/connection_adapters/sqlserver/version.rb
index ac48b9c..4ab2d25 100644
--- a/lib/active_record/connection_adapters/sqlserver/version.rb
+++ b/lib/active_record/connection_adapters/sqlserver/version.rb
@@ -3,7 +3,7 @@ module ActiveRecord
     module Sqlserver
       module Version
         
-        VERSION = '3.1.2'.freeze
+        VERSION = '3.1.2'
         
       end
     end
diff --git a/lib/active_record/connection_adapters/sqlserver_adapter.rb b/lib/active_record/connection_adapters/sqlserver_adapter.rb
index f47f78c..f9f74de 100644
--- a/lib/active_record/connection_adapters/sqlserver_adapter.rb
+++ b/lib/active_record/connection_adapters/sqlserver_adapter.rb
@@ -53,7 +53,7 @@ module ActiveRecord
       def initialize(name, default, sql_type = nil, null = true, sqlserver_options = {})
         @sqlserver_options = sqlserver_options.symbolize_keys
         super(name, default, sql_type, null)
-        @primary = @sqlserver_options[:is_identity]
+        @primary = @sqlserver_options[:is_primary_key]
       end
       
       class << self