new usage of builder

`

12 files changed, 149 insertions, 78 deletions

diff --git a/lib/sql_algebra.rb b/lib/sql_algebra.rb
index 5753a48d2f..b3e3c8d176 100644
--- a/lib/sql_algebra.rb
+++ b/lib/sql_algebra.rb
@@ -1,8 +1,10 @@
 $LOAD_PATH.unshift(File.dirname(__FILE__))
 require 'rubygems'
-require 'active_support'
+require 'activesupport'
+require 'activerecord'
 
 require 'sql_algebra/relations/relation'
+require 'sql_algebra/relations/compound_relation'
 require 'sql_algebra/relations/table_relation'
 require 'sql_algebra/relations/join_operation'
 require 'sql_algebra/relations/inner_join_operation'
@@ -15,6 +17,7 @@ require 'sql_algebra/relations/projection_relation'
 require 'sql_algebra/relations/selection_relation'
 require 'sql_algebra/relations/order_relation'
 require 'sql_algebra/relations/range_relation'
+require 'sql_algebra/relations/join'
 
 require 'sql_algebra/predicates/predicate'
 require 'sql_algebra/predicates/binary_predicate'
@@ -30,7 +33,6 @@ require 'sql_algebra/predicates/match_predicate'
 require 'sql_algebra/extensions/range'
 require 'sql_algebra/extensions/object'
 
-require 'sql_algebra/sql_builder/sql_builder_adapter'
 require 'sql_algebra/sql_builder/sql_builder'
 require 'sql_algebra/sql_builder/select_builder'
 require 'sql_algebra/sql_builder/joins_builder'
diff --git a/lib/sql_algebra/extensions/base.rb b/lib/sql_algebra/extensions/base.rb
new file mode 100644
index 0000000000..79f2ce75d1
--- /dev/null
+++ b/lib/sql_algebra/extensions/base.rb
@@ -0,0 +1,15 @@
+class ActiveRecord::Base
+  def self.bring_forth(record, includes = [])
+    object = cache.get(record % klass.primary_key) { Klass.instantiate(record % Klass.attributes) }
+    includes.each do |include|
+      case include
+        when Symbol
+          object.send(association = include).bring_forth(record)
+        when Hash
+          include.each do |association, nested_associations|
+            object.send(association).bring_forth(record, nested_associations)
+          end
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/sql_algebra/extensions/object.rb b/lib/sql_algebra/extensions/object.rb
new file mode 100644
index 0000000000..639e810a97
--- /dev/null
+++ b/lib/sql_algebra/extensions/object.rb
@@ -0,0 +1,8 @@
+class Object
+  def to_sql(builder = EqualsConditionBuilder.new)
+    me = self
+    builder.call do
+      value me
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/inner_join_relation.rb b/lib/sql_algebra/relations/inner_join_relation.rb
index 1ef965a6f5..6b932e3b21 100644
--- a/lib/sql_algebra/relations/inner_join_relation.rb
+++ b/lib/sql_algebra/relations/inner_join_relation.rb
@@ -1,5 +1,5 @@
 class InnerJoinRelation < JoinRelation
-  def join_name
+  def join_type
     :inner_join
   end
 end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/join_relation.rb b/lib/sql_algebra/relations/join_relation.rb
index b96cd175de..dc57e24c96 100644
--- a/lib/sql_algebra/relations/join_relation.rb
+++ b/lib/sql_algebra/relations/join_relation.rb
@@ -11,24 +11,22 @@ class JoinRelation < Relation
       (relation2 == other.relation1 and relation1 == other.relation2))
   end
   
-  def to_sql(builder = SelectBuilder.new)
-    relation2.to_sql(translate_from_to_inner_join_on_predicates(relation1.to_sql(builder)))
+  def joins
+    relation1.joins + relation2.joins + [Join.new(relation1, relation2, predicates, join_type)]
   end
   
-  private
-  # translate 'from' to 'inner join on <predicates>'
-  def translate_from_to_inner_join_on_predicates(builder)
-    schmoin_name, schmredicates = join_name, predicates
-    SqlBuilderAdapter.new(builder) do |builder|
-      define_method :from do |table|
-        builder.call do
-          send(schmoin_name, table) do
-            schmredicates.each do |predicate|
-              predicate.to_sql(self)
-            end
-          end
-        end
-      end
-    end
+  def selects
+    relation1.selects + relation2.selects
   end
+  
+  def attributes
+    relation1.attributes + relation2.attributes
+  end
+  
+  def attribute(name)
+    relation1[name] || relation2[name]
+  end
+  
+  protected
+  delegate :table, :to => :relation1
 end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/left_outer_join_relation.rb b/lib/sql_algebra/relations/left_outer_join_relation.rb
index c7722c394d..f4ece43861 100644
--- a/lib/sql_algebra/relations/left_outer_join_relation.rb
+++ b/lib/sql_algebra/relations/left_outer_join_relation.rb
@@ -1,5 +1,5 @@
 class LeftOuterJoinRelation < JoinRelation
-  def join_name
+  def join_type
     :left_outer_join
   end
 end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/relation.rb b/lib/sql_algebra/relations/relation.rb
index bd812b368d..8c21927d01 100644
--- a/lib/sql_algebra/relations/relation.rb
+++ b/lib/sql_algebra/relations/relation.rb
@@ -1,34 +1,65 @@
 class Relation
-  def <=>(other)
-    InnerJoinOperation.new(self, other)
-  end
+  module Operations
+    def <=>(other)
+      InnerJoinOperation.new(self, other)
+    end
   
-  def <<(other)
-    LeftOuterJoinOperation.new(self, other)
-  end
+    def <<(other)
+      LeftOuterJoinOperation.new(self, other)
+    end
   
-  def [](index)
-    case index
-    when Symbol
-      Attribute.new(self, index)
-    when Range
-      RangeRelation.new(self, index)
+    def [](index)
+      case index
+      when Symbol
+        attribute(index)
+      when Range
+        RangeRelation.new(self, index)
+      end
     end
-  end
   
-  def include?(attribute)
-    RelationInclusionPredicate.new(attribute, self)
-  end
+    def include?(attribute)
+      RelationInclusionPredicate.new(attribute, self)
+    end
   
-  def select(*predicates)
-    SelectionRelation.new(self, *predicates)
+    def select(*predicates)
+      SelectionRelation.new(self, *predicates)
+    end
+  
+    def project(*attributes)
+      ProjectionRelation.new(self, *attributes)
+    end
+  
+    def order(*attributes)
+      OrderRelation.new(self, *attributes)
+    end
   end
+  include Operations
   
-  def project(*attributes)
-    ProjectionRelation.new(self, *attributes)
+  def connection
+    ActiveRecord::Base.connection
   end
   
-  def order(*attributes)
-    OrderRelation.new(self, *attributes)
+  def to_sql(builder = SelectBuilder.new)
+    builder.call do
+      select do
+        attributes.each { |a| a.to_sql(self) }
+      end
+      from table do
+        joins.each { |j| j.to_sql(self) }
+      end
+      where do
+        selects.each { |s| s.to_sql(self) }
+      end
+      order_by do
+        orders.each { |o| o.to_sql(self) }
+      end
+    end
   end
+  
+  protected
+  def attributes; [] end
+  def joins;      [] end
+  def selects;    [] end
+  def orders;     [] end
+            
 end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/selection_relation.rb b/lib/sql_algebra/relations/selection_relation.rb
index 51461de7d2..72911aa65a 100644
--- a/lib/sql_algebra/relations/selection_relation.rb
+++ b/lib/sql_algebra/relations/selection_relation.rb
@@ -1,4 +1,4 @@
-class SelectionRelation < Relation
+class SelectionRelation < CompoundRelation
   attr_reader :relation, :predicate
   
   def initialize(relation, *predicates)
@@ -10,13 +10,7 @@ class SelectionRelation < Relation
     relation == other.relation and predicate == other.predicate
   end
   
-  def to_sql(builder = SelectBuilder.new)
-    relation.to_sql(builder).call do
-      where do
-        predicate.to_sql(self)
-      end
-    end
+  def selects
+    [predicate]
   end
-  
-  delegate :[], :to => :relation
 end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/table_relation.rb b/lib/sql_algebra/relations/table_relation.rb
index 60bdfda8ee..1915b42565 100644
--- a/lib/sql_algebra/relations/table_relation.rb
+++ b/lib/sql_algebra/relations/table_relation.rb
@@ -5,10 +5,19 @@ class TableRelation < Relation
     @table = table
   end
   
-  def to_sql(builder = SelectBuilder.new)
-    builder.call do
-      select { all }
-      from table
+  def attributes
+    attributes_by_name.values
+  end
+    
+  protected
+  def attribute(name)
+    attributes_by_name[name.to_s]
+  end
+  
+  private
+  def attributes_by_name
+    @attributes_by_name ||= connection.columns(table, "#{table} Columns").inject({}) do |attributes_by_name, column|
+      attributes_by_name.merge(column.name => Attribute.new(self, column.name.to_sym))
     end
   end
 end
\ No newline at end of file
diff --git a/lib/sql_algebra/sql_builder/order_builder.rb b/lib/sql_algebra/sql_builder/order_builder.rb
new file mode 100644
index 0000000000..4eea40fa36
--- /dev/null
+++ b/lib/sql_algebra/sql_builder/order_builder.rb
@@ -0,0 +1,16 @@
+class OrderBuilder < SqlBuilder
+  def initialize(&block)
+    @orders = []
+    super(&block)
+  end
+  
+  def column(table, column, aliaz = nil)
+    @orders << (aliaz ? aliaz : "#{table}.#{column}")
+  end
+  
+  def to_s
+    @orders.join(', ')
+  end
+  
+  delegate :blank?, :to => :@orders
+end
\ No newline at end of file
diff --git a/lib/sql_algebra/sql_builder/selects_builder.rb b/lib/sql_algebra/sql_builder/selects_builder.rb
new file mode 100644
index 0000000000..72f6f52397
--- /dev/null
+++ b/lib/sql_algebra/sql_builder/selects_builder.rb
@@ -0,0 +1,20 @@
+class SelectsBuilder < SqlBuilder
+  def initialize(&block)
+    @selects = []
+    super(&block)
+  end
+  
+  def to_s
+    @selects.join(', ')
+  end
+  
+  def all
+    @selects << :*
+  end
+  
+  def column(table, column, aliaz = nil)
+    @selects << "#{table}.#{column}" + (aliaz ? " AS #{aliaz}" : '')
+  end
+  
+  delegate :blank?, :to => :@selects
+end
\ No newline at end of file
diff --git a/lib/sql_algebra/sql_builder/sql_builder_adapter.rb b/lib/sql_algebra/sql_builder/sql_builder_adapter.rb
deleted file mode 100644
index 9bb5271f33..0000000000
--- a/lib/sql_algebra/sql_builder/sql_builder_adapter.rb
+++ /dev/null
@@ -1,22 +0,0 @@
-class SqlBuilderAdapter
-  instance_methods.each { |m| undef_method m unless m =~ /^__|^instance_eval|class/ }
-    
-  def initialize(adaptee, &block)
-    @adaptee = adaptee
-    (class << self; self end).class_eval do
-      (adaptee.methods - instance_methods).each { |m| delegate m, :to => :@adaptee }
-    end
-    (class << self; self end).instance_exec(@adaptee, &block)
-  end
-  
-  def call(&block)
-    @caller = eval("self", block.binding)
-    returning self do |adapter|
-      instance_eval(&block)
-    end
-  end
-  
-  def method_missing(method, *args, &block)
-    @caller.send(method, *args, &block)
-  end
-end
\ No newline at end of file