Index: branches/ast/geniusql/dbtypes.py
===================================================================
--- branches/ast/geniusql/dbtypes.py (revision 119)
+++ branches/ast/geniusql/dbtypes.py (revision 128)
@@ -48,14 +48,19 @@
     def default_adapter(self, pytype):
         """Return a default adapter instance for the given pytype, dbtype."""
-        ptypes = [pytype, None]
-        for base in pytype.__bases__:
-            ptypes.append(base)
-        
-        for p in ptypes:
-            if p in self.default_adapters:
-                return self.default_adapters[p]
-        
-        raise TypeError("%s has no default adapter for %s. Looked for: %s" %
-                        (self, pytype, ", ".join([repr(x) for x in ptypes])))
+        # Use try for the common case where the pytype is in the dict.
+        try:
+            return self.default_adapters[pytype]
+        except KeyError:
+            defaults = self.default_adapters
+            if None in defaults:
+                return defaults[None]
+            for p in pytype.__bases__:
+                if p in defaults:
+                    return defaults[p]
+        
+        raise TypeError("%s has no default adapter for %s. Looked for: "
+                        "%s, None, %s" %
+                        (self, pytype, pytype,
+                         ", ".join([repr(x) for x in ptype.__bases__])))
 
 
Index: branches/ast/geniusql/deparse.py
===================================================================
--- branches/ast/geniusql/deparse.py (revision 124)
+++ branches/ast/geniusql/deparse.py (revision 128)
@@ -48,8 +48,5 @@
     
     def __cmp__(self, other):
-        if isinstance(other, SQLExpression):
-            return cmp(self.sql, other.sql)
-        raise TypeError("can't compare %s to %s" % (type(self), type(other)),
-                        other)
+        return cmp(self.sql, other.sql)
     
     def __repr__(self):
@@ -152,8 +149,6 @@
         """Return an SQLExpression for the given sql of the given pytype."""
         self.exprcount += 1
-        name = "expr%s" % self.exprcount
-        
         dbtype = self.typeset.database_type(pytype)
-        e = SQLExpression(sql, name, dbtype, pytype)
+        e = SQLExpression(sql, "expr%s" % self.exprcount, dbtype, pytype)
         e.adapter = adapter or dbtype.default_adapter(pytype)
         return e
Index: branches/ast/geniusql/select.py
===================================================================
--- branches/ast/geniusql/select.py (revision 126)
+++ branches/ast/geniusql/select.py (revision 128)
@@ -240,10 +240,26 @@
                     alias = t.alias or t.qname
                     table = t.table
-                    for a in attrs:
-                        self._copy_column(table, alias, a)
+                    for colkey in attrs:
+                        col = table[colkey]
+                        if colkey in self.output_cols:
+                            # Get the key for the table.
+                            colkey = '%s_%s' % (table.schema.key_for(table), colkey)
+                            colname = '%s_%s' % (alias, col.name)
+                            colqname = self.db.quote(colname)
+                            selname = '%s.%s AS %s' % (alias, col.qname, colqname)
+                        else:
+                            colname = col.name
+                            colqname = col.qname
+                            selname = '%s.%s' % (alias, colqname)
+                        self.input_list.append(selname)
+                        self.output.append((colkey, colname, colqname))
+                        self.output_cols[colkey] = col
             else:
                 # 'relation' is a single Table object.
-                for a in query.attributes:
-                    self._copy_column(relation, None, a)
+                for colkey in query.attributes:
+                    col = relation[colkey]
+                    self.input_list.append(col.qname)
+                    self.output.append((colkey, col.name, col.qname))
+                    self.output_cols[colkey] = col
         
         if query.order is None:
@@ -278,33 +294,4 @@
             newtable[colkey] = newcol
         return newtable
-    
-    def _copy_column(self, table, alias, colkey):
-        """Copy the given column from the given table into our result table.
-        
-        alias: the name that will be used for the given source table in the
-            FROM clause of the SQL SELECT statement. If None, this signifies
-            that the "SELECT columnlist FROM table" only references a single
-            table, in which case the column list will not use dotted column
-            names.
-        """
-        col = table[colkey]
-        
-        colname = col.name
-        colqname = col.qname
-        if alias is None:
-            # Single table.
-            selname = colqname
-        else:
-            selname = '%s.%s' % (alias, colqname)
-        
-        if colkey in self.output_cols:
-            # Get the key for the table.
-            colkey = '%s_%s' % (table.schema.key_for(table), colkey)
-            colname = '%s_%s' % (table.name, colname)
-            colqname = self.db.quote(colname)
-            selname = '%s AS %s' % (selname, colqname)
-        self.input_list.append(selname)
-        self.output.append((colkey, colname, colqname))
-        self.output_cols[colkey] = col
     
     def sql(self, distinct=False, limit=None, into=""):