Sql Bulk Insert/Update

CREATE PROC AlterSomeObj
 @act VARCHAR(10) = 'C',    
 @objXML xml     
AS    
    
IF (@act = 'C')    -- for creating
BEGIN    
    
 INSERT Table1(val1, val2)    
 SELECT     
    
  ITEM.TAB.value('val1[1]','VARCHAR(1000)') AS val1 ,    
  ITEM.TAB.value('val2[1]','VARCHAR(MAX)') AS val2 ,    
  FROM @objXML.nodes('ParentNode/ChildNode') ITEM(TAB)    
    
END    
ELSE IF(@act = 'U')     -- for updating
BEGIN    
 U Table1    
 SET     
 val1 = TAB.val1 ,     
 val2 = TAB.val2,    
    
 FROM     
  Table1 ITEMITEMS    
  INNER JOIN    
  (    
   SELECT    
    ITEM.TAB.value('val1[1]','VARCHAR(1000)') AS val1 ,    
    ITEM.TAB.value('val2[1]','VARCHAR(MAX)') AS val2 
    
   FROM @objXML.nodes('ParentNode/ChildNode') ITEM(TAB)    
  )TAB    
    
 ON ITEMITEMS.ID = @urlID    
   
    
END    
ELSE IF(@act = 'D')    -- for deleting
BEGIN    
--delete logic
END