From 17080aa38149dcede39ed52766a0c2bd624f8a62 Mon Sep 17 00:00:00 2001
From: LtWorf <LtWorf@014f5005-505e-4b48-8d0a-63407b615a7c>
Date: Wed, 13 May 2009 14:06:42 +0000
Subject: [PATCH] fixed problem with select and renames when using fields

git-svn-id: http://galileo.dmi.unict.it/svn/relational/trunk@171 014f5005-505e-4b48-8d0a-63407b615a7c
---
 relational/optimizations.py | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/relational/optimizations.py b/relational/optimizations.py
index 9a877cf..0b348eb 100644
--- a/relational/optimizations.py
+++ b/relational/optimizations.py
@@ -213,7 +213,6 @@ def swap_rename_select(n):
     them with ρ j(σ k(R)). Renaming the attributes used in the
     selection, so the operation is still valid.'''
     #TODO document into the wiki
-    #FIXME selection of date.day won't work.
     changes=0
     
     if n.name=='σ' and n.child.name=='ρ':
@@ -229,8 +228,12 @@ def swap_rename_select(n):
         
         #Renaming stuff
         for i in range(len(_tokens)):
-            if _tokens[i] in _vars:
-                _tokens[i]=_vars[_tokens[i]]
+            splitted=_tokens[i].split('.',1)
+            if splitted[0] in _vars:
+                if len(splitted)==1:
+                    _tokens[i]=_vars[_tokens[i].split('.')[0]]
+                else:
+                    _tokens[i]=_vars[_tokens[i].split('.')[0]]+'.'+splitted[1]
         
         #Swapping operators
         n.name='ρ'