various

14 files changed, 45 insertions, 50 deletions

diff --git a/lib/sql_algebra/relations/order_relation.rb b/lib/sql_algebra/relations/order_relation.rb
new file mode 100644
index 0000000000..8d07c58d64
--- /dev/null
+++ b/lib/sql_algebra/relations/order_relation.rb
@@ -0,0 +1,11 @@
+class OrderRelation < Relation
+  attr_reader :relation, :attributes
+  
+  def initialize(relation, *attributes)
+    @relation, @attributes = relation, attributes
+  end
+  
+  def ==(other)
+    relation == other.relation and attributes.eql?(other.attributes)
+  end
+end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/predicates/binary_predicate.rb b/lib/sql_algebra/relations/predicates/binary_predicate.rb
deleted file mode 100644
index d7f4cb20e7..0000000000
--- a/lib/sql_algebra/relations/predicates/binary_predicate.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-class BinaryPredicate < Predicate
-  attr_reader :attribute1, :attribute2
-  
-  def initialize(attribute1, attribute2)
-    @attribute1, @attribute2 = attribute1, attribute2
-  end
-  
-  def ==(other)
-    super and
-      (attribute1.eql?(other.attribute1) and attribute2.eql?(other.attribute2))
-  end
-end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/predicates/equality_predicate.rb b/lib/sql_algebra/relations/predicates/equality_predicate.rb
deleted file mode 100644
index 2d206e6c12..0000000000
--- a/lib/sql_algebra/relations/predicates/equality_predicate.rb
+++ /dev/null
@@ -1,7 +0,0 @@
-class EqualityPredicate < BinaryPredicate
-  def ==(other)
-    self.class == other.class and
-      ((attribute1.eql?(other.attribute1) and attribute2.eql?(other.attribute2)) or
-       (attribute1.eql?(other.attribute2) and attribute2.eql?(other.attribute1)))
-  end
-end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/predicates/greater_than_or_equal_to_predicate.rb b/lib/sql_algebra/relations/predicates/greater_than_or_equal_to_predicate.rb
deleted file mode 100644
index 49127c312c..0000000000
--- a/lib/sql_algebra/relations/predicates/greater_than_or_equal_to_predicate.rb
+++ /dev/null
@@ -1,2 +0,0 @@
-class GreaterThanOrEqualToPredicate < BinaryPredicate
-end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/predicates/greater_than_predicate.rb b/lib/sql_algebra/relations/predicates/greater_than_predicate.rb
deleted file mode 100644
index 03aecaed62..0000000000
--- a/lib/sql_algebra/relations/predicates/greater_than_predicate.rb
+++ /dev/null
@@ -1,2 +0,0 @@
-class GreaterThanPredicate < BinaryPredicate
-end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/predicates/less_than_or_equal_to_predicate.rb b/lib/sql_algebra/relations/predicates/less_than_or_equal_to_predicate.rb
deleted file mode 100644
index fee6ea7f35..0000000000
--- a/lib/sql_algebra/relations/predicates/less_than_or_equal_to_predicate.rb
+++ /dev/null
@@ -1,2 +0,0 @@
-class LessThanOrEqualToPredicate < BinaryPredicate
-end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/predicates/less_than_predicate.rb b/lib/sql_algebra/relations/predicates/less_than_predicate.rb
deleted file mode 100644
index 03cbdcf000..0000000000
--- a/lib/sql_algebra/relations/predicates/less_than_predicate.rb
+++ /dev/null
@@ -1,2 +0,0 @@
-class LessThanPredicate < BinaryPredicate
-end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/predicates/match_predicate.rb b/lib/sql_algebra/relations/predicates/match_predicate.rb
deleted file mode 100644
index 90a13090d4..0000000000
--- a/lib/sql_algebra/relations/predicates/match_predicate.rb
+++ /dev/null
@@ -1,7 +0,0 @@
-class MatchPredicate < Predicate
-  attr_reader :attribute, :regexp
-  
-  def initialize(attribute, regexp)
-    @attribute, @regexp = attribute, regexp
-  end
-end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/predicates/predicate.rb b/lib/sql_algebra/relations/predicates/predicate.rb
deleted file mode 100644
index 4c395a3fdc..0000000000
--- a/lib/sql_algebra/relations/predicates/predicate.rb
+++ /dev/null
@@ -1,5 +0,0 @@
-class Predicate
-  def ==(other)
-    self.class == other.class
-  end
-end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/predicates/range_inclusion_predicate.rb b/lib/sql_algebra/relations/predicates/range_inclusion_predicate.rb
deleted file mode 100644
index e69de29bb2..0000000000
--- a/lib/sql_algebra/relations/predicates/range_inclusion_predicate.rb
+++ /dev/null
diff --git a/lib/sql_algebra/relations/predicates/relation_inclusion_predicate.rb b/lib/sql_algebra/relations/predicates/relation_inclusion_predicate.rb
deleted file mode 100644
index 5881a85d99..0000000000
--- a/lib/sql_algebra/relations/predicates/relation_inclusion_predicate.rb
+++ /dev/null
@@ -1,11 +0,0 @@
-class RelationInclusionPredicate < Predicate
-  attr_reader :attribute, :relation
-  
-  def initialize(attribute, relation)
-    @attribute, @relation = attribute, relation
-  end
-  
-  def ==(other)
-    super and attribute == other.attribute and relation == other.relation
-  end
-end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/projection_relation.rb b/lib/sql_algebra/relations/projection_relation.rb
new file mode 100644
index 0000000000..caebfc1b62
--- /dev/null
+++ b/lib/sql_algebra/relations/projection_relation.rb
@@ -0,0 +1,11 @@
+class ProjectionRelation < Relation
+  attr_reader :relation, :attributes
+  
+  def initialize(relation, *attributes)
+    @relation, @attributes = relation, attributes
+  end
+  
+  def ==(other)
+    relation == other.relation and attributes.eql?(other.attributes)
+  end
+end
\ No newline at end of file
diff --git a/lib/sql_algebra/relations/range_relation.rb b/lib/sql_algebra/relations/range_relation.rb
new file mode 100644
index 0000000000..fd7e2898fa
--- /dev/null
+++ b/lib/sql_algebra/relations/range_relation.rb
@@ -0,0 +1,11 @@
+class RangeRelation < Relation
+  attr_reader :relation, :range
+  
+  def initialize(relation, range)
+    @relation, @range = relation, range
+  end
+  
+  def ==(other)
+    relation == other.relation and range == other.range
+  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
new file mode 100644
index 0000000000..5654d8de31
--- /dev/null
+++ b/lib/sql_algebra/relations/selection_relation.rb
@@ -0,0 +1,12 @@
+class SelectionRelation < Relation
+  attr_reader :relation, :predicate
+  
+  def initialize(relation, *predicates)
+    @predicate = predicates.shift
+    @relation = predicates.empty?? relation : SelectionRelation.new(relation, *predicates)
+  end
+  
+  def ==(other)
+    relation == other.relation and predicate == other.predicate
+  end
+end
\ No newline at end of file