Condition pushdown to storage engine, optimizations

sql/ha_ndbcluster.cc

@@ -5426,8 +5426,6 @@ void ndb_serialize_cond(const Item *item, void *arg)
       if (context->table == field->table)
       {	
 	const NDBTAB *tab= (const NDBTAB *) context->ndb_table;
-	const NDBCOL *col= tab->getColumn(field->field_name);
-	DBUG_ASSERT(col);
 	DBUG_PRINT("info", ("FIELD_ITEM"));
 	DBUG_PRINT("info", ("table %s", tab->getName()));
 	DBUG_PRINT("info", ("column %s", field->field_name));
@@ -5442,6 +5440,8 @@ void ndb_serialize_cond(const Item *item, void *arg)
 	    *context->supported_ptr= FALSE;  
 	  else
 	  {
+	    const NDBCOL *col= tab->getColumn(field->field_name);
+	    DBUG_ASSERT(col);
 	    curr_cond->ndb_item= new Ndb_item(field, col->getColumnNo());
 	    context->dont_expect(Item::FIELD_ITEM);
 	    context->expect_no_field_result();

sql/item_cmpfunc.cc

@@ -2044,12 +2044,21 @@ void Item_cond::traverse_cond(Item_cond_traverser traverser,
   List_iterator<Item> li(list);
   Item *item;
 
-  if (order == PREFIX) (*traverser)(this, arg);
-  while ((item= li++))
-  {
-    item->traverse_cond(traverser, arg, order);
+  switch(order) {
+  case(PREFIX):
+    (*traverser)(this, arg);
+    while ((item= li++))
+    {
+      item->traverse_cond(traverser, arg, order);
+    }
+    break;
+  case(POSTFIX):
+    while ((item= li++))
+    {
+      item->traverse_cond(traverser, arg, order);
+    }
+    (*traverser)(this, arg);
   }
-  if (order == POSTFIX) (*traverser)(this, arg);
 }
 
 void Item_cond::split_sum_func(THD *thd, Item **ref_pointer_array,

sql/item_func.cc

@@ -349,13 +349,23 @@ void Item_func::traverse_cond(Item_cond_traverser traverser,
   if (arg_count)
   {
     Item **arg,**arg_end;
-    if (order == PREFIX) (traverser)(this, argument);
-    for (arg= args, arg_end= args+arg_count; arg != arg_end; arg++)
-    {
-      (*arg)->traverse_cond(traverser, argument, order);
+
+    switch (order) {
+    case(PREFIX):
+      (traverser)(this, argument);
+      for (arg= args, arg_end= args+arg_count; arg != arg_end; arg++)
+      {
+	(*arg)->traverse_cond(traverser, argument, order);
+      }
+      break;
+    case (POSTFIX):
+      for (arg= args, arg_end= args+arg_count; arg != arg_end; arg++)
+      {
+	(*arg)->traverse_cond(traverser, argument, order);
+      }
+      (traverser)(this, argument);
     }
   }
-  if (order == POSTFIX) (traverser)(this, argument);
 }