1 files changed, 39 insertions, 0 deletions
diff --git a/lib/arel/engines/sql/relations/writes.rb b/lib/arel/engines/sql/relations/writes.rb
new file mode 100644
index 0000000000..f1a9bfd2ac
--- /dev/null
+++ b/lib/arel/engines/sql/relations/writes.rb
@@ -0,0 +1,39 @@
+module Arel
+  class Deletion < Compound
+    def to_sql(formatter = nil)
+      build_query \
+        "DELETE",
+        "FROM #{table_sql}",
+        ("WHERE #{wheres.collect(&:to_sql).join('\n\tAND ')}" unless wheres.blank? ),
+        ("LIMIT #{taken}"                                     unless taken.blank?  )
+    end
+  end
+
+  class Insert < Compound
+    def to_sql(formatter = nil)
+      build_query \
+        "INSERT",
+        "INTO #{table_sql}",
+        "(#{record.keys.collect { |key| engine.quote_column_name(key.name) }.join(', ')})",
+        "VALUES (#{record.collect { |key, value| key.format(value) }.join(', ')})"
+    end
+  end
+
+  class Update < Compound
+    def to_sql(formatter = nil)
+      build_query \
+        "UPDATE #{table_sql} SET",
+        assignment_sql,
+        ("WHERE #{wheres.collect(&:to_sql).join('\n\tAND ')}"  unless wheres.blank? ),
+        ("LIMIT #{taken}"                                      unless taken.blank?  )
+    end
+
+  protected
+
+    def assignment_sql
+      assignments.collect do |attribute, value|
+        "#{engine.quote_column_name(attribute.name)} = #{attribute.format(value)}"
+      end.join(",\n")
+    end
+  end
+end