Added new Migrations framework for describing schema transformations in a way that can be easily applied across multiple databases #1604 [Tobias Luetke]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@1672 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 40 insertions, 5 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index 1137ea1011..1b5c8184ae 100755
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -357,9 +357,10 @@ module ActiveRecord
         sql << " OFFSET #{options[:offset]}" if options.has_key?(:offset) and !options[:offset].nil?
       end
 
+
       def initialize_schema_information
         begin
-          execute "CREATE TABLE schema_info (version #{native_database_types[:integer][:name]}(#{native_database_types[:integer][:limit]}))"
+          execute "CREATE TABLE schema_info (version #{type_to_sql(:integer)})"
           insert "INSERT INTO schema_info (version) VALUES(0)"
         rescue ActiveRecord::StatementInvalid
           # Schema has been intialized
@@ -378,8 +379,7 @@ module ActiveRecord
 
       def add_column(table_name, column_name, type, options = {})
         native_type = native_database_types[type]
-        add_column_sql = "ALTER TABLE #{table_name} ADD #{column_name} #{native_type[:name]}"
-        add_column_sql << "(#{options[:limit] || native_type[:limit]})" if options[:limit] || native_type[:limit]
+        add_column_sql = "ALTER TABLE #{table_name} ADD #{column_name} #{type_to_sql(type)}"
         add_column_sql << " DEFAULT '#{options[:default]}'" if options[:default]
         execute(add_column_sql)
       end
@@ -387,9 +387,20 @@ module ActiveRecord
       def remove_column(table_name, column_name)
         execute "ALTER TABLE #{table_name} DROP #{column_name}"
       end
+      
+      def supports_migrations?
+        false
+      end      
 
 
       protected
+        def type_to_sql(type)
+          native = native_database_types[type]
+          column_type_sql = native[:name]
+          column_type_sql << "(#{native[:limit]})" if native[:limit]
+          column_type_sql
+        end            
+              
         def log(sql, name)
           begin
             if block_given?
@@ -439,7 +450,7 @@ module ActiveRecord
             "%s  %s" % [message, dump]
           end
         end
-    end
+      end
 
     class TableDefinition
       attr_accessor :columns
diff --git a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
index ad0e490194..ec0558a4d5 100755
--- a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
@@ -63,6 +63,10 @@ module ActiveRecord
         "Lost connection to MySQL server during query",
         "MySQL server has gone away"
       ]
+      
+      def supports_migrations?
+        true
+      end
 
       def native_database_types
         {
@@ -89,7 +93,6 @@ module ActiveRecord
         'MySQL'
       end
 
-
       def select_all(sql, name = nil)
         select(sql, name)
       end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index 66cbe3a58b..3d6550ea9a 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -60,6 +60,27 @@ module ActiveRecord
     # * <tt>:encoding</tt> -- An optional client encoding that is using in a SET client_encoding TO <encoding> call on connection.
     # * <tt>:min_messages</tt> -- An optional client min messages that is using in a SET client_min_messages TO <min_messages> call on connection.
     class PostgreSQLAdapter < AbstractAdapter
+      
+      def native_database_types
+        {
+          :primary_key => "serial primary key",
+          :string      => { :name => "character varying", :limit => 255 },
+          :text        => { :name => "text" },
+          :integer     => { :name => "integer" },
+          :float       => { :name => "float" },
+          :datetime    => { :name => "timestamp" },
+          :timestamp   => { :name => "timestamp" },
+          :time        => { :name => "timestamp" },
+          :date        => { :name => "date" },
+          :binary      => { :name => "bytea" },
+          :boolean     => { :name => "boolean"}
+        }
+      end
+      
+      def supports_migrations?
+        true
+      end      
+      
       def select_all(sql, name = nil)
         select(sql, name)
       end