Update DB2 adapter. Closes #2206.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@2546 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 38 insertions, 2 deletions

diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG
index d38390110f..5f3c738b77 100644
--- a/activerecord/CHANGELOG
+++ b/activerecord/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Update DB2 adapter. #2206. [contact@maik-schmidt.de]
+
 * Corrections to SQLServer native data types. #2267.  [rails.20.clarry@spamgourmet.com]
 
 * Deprecated ActiveRecord::Base.threaded_connection in favor of ActiveRecord::Base.allow_concurrency.
diff --git a/activerecord/lib/active_record/connection_adapters/db2_adapter.rb b/activerecord/lib/active_record/connection_adapters/db2_adapter.rb
index 58dd04a784..ab13494153 100644
--- a/activerecord/lib/active_record/connection_adapters/db2_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/db2_adapter.rb
@@ -92,8 +92,25 @@ begin
         end
 
         def add_limit_offset!(sql, options)
-          sql << " FETCH FIRST #{options[:limit]} ROWS ONLY" if options[:limit] and !options[:limit].nil?
-          raise ArgumentError, 'add_limit_offset! not implemented.' if options[:offset] and !options[:offset].nil?
+          if options[:limit] and !options[:limit].nil?
+            # "FETCH FIRST 0 ROWS ONLY" is not allowed, so we have
+            # to use a cheap trick.
+            if options[:limit] == 0
+              if sql =~ /WHERE/i
+                sql.sub!(/WHERE/i, 'WHERE 1 = 2 AND ')
+              elsif
+                sql =~ /ORDER\s+BY/i
+                sql.sub!(/ORDER\s+BY/i, 'WHERE 1 = 2 ORDER BY')
+              else
+                sql << 'WHERE 1 = 2'
+              end
+            else
+              sql << " FETCH FIRST #{options[:limit]} ROWS ONLY" 
+            end
+          end
+          if options[:offset] and !options[:offset].nil?
+            raise ArgumentError, ':offset option is not yet supported!'
+          end
         end
 
         def columns(table_name, name = nil)
@@ -112,6 +129,22 @@ begin
           result
         end
 
+        def native_database_types
+          {
+            :primary_key => "int generated by default as identity primary key",
+            :string      => { :name => "varchar", :limit => 255 },
+            :text        => { :name => "clob", :limit => 32768 },
+            :integer     => { :name => "int" },
+            :float       => { :name => "float" },
+            :datetime    => { :name => "timestamp" },
+            :timestamp   => { :name => "timestamp" },
+            :time        => { :name => "time" },
+            :date        => { :name => "date" },
+            :binary      => { :name => "blob", :limit => 32768 },
+            :boolean     => { :name => "decimal", :limit => 1 }
+          }
+        end
+
         private
 
         def last_insert_id
diff --git a/activerecord/test/fixtures/db_definitions/db2.drop.sql b/activerecord/test/fixtures/db_definitions/db2.drop.sql
index 07bffb6019..b0ff4b94c6 100644
--- a/activerecord/test/fixtures/db_definitions/db2.drop.sql
+++ b/activerecord/test/fixtures/db_definitions/db2.drop.sql
@@ -4,6 +4,7 @@ DROP TABLE topics;
 DROP TABLE developers;
 DROP TABLE projects;
 DROP TABLE developers_projects;
+DROP TABLE orders;
 DROP TABLE customers;
 DROP TABLE orders;
 DROP TABLE movies;