now handles more than 2 nested selections

git-svn-id: http://galileo.dmi.unict.it/svn/relational/trunk@137 014f5005-505e-4b48-8d0a-63407b615a7c

relational/optimizations.py

@@ -30,6 +30,7 @@ def duplicated_select(n):
         if n.prop != n.child.prop: #Nested but different, joining them
             n.prop = n.prop + " and " + n.child.prop
         n.child=n.child.child
+        duplicated_select(n)
 
     #recoursive scan
     if n.kind==optimizer.UNARY:

relational/optimizer.py

@@ -177,7 +177,7 @@ if __name__=="__main__":
     #a= tokenize("(a - (a ᑌ b) * π a,b (a-b)) - ρ 123 (a)")
     #a= tokenize(u"π a,b (a*b)")
     #a=tokenize("(a-b*c)*(b-c)")
-    a=general_optimize("σ b>5 ( σ a>2 (C)) * σ a>2 ( σ a>2 (C))")
+    a=general_optimize("σ i==2 (σ b>5 ( σ a>2 (C))) * σ a>2 ( σ a>2 (C))")
     print a
     #print node(a)
     #print tokenize("(a)")