diff --git a/AstuteSystem/sql/astute.sql b/AstuteSystem/sql/astute.sql
index db0b0b8..3ac8be4 100644
--- a/AstuteSystem/sql/astute.sql
+++ b/AstuteSystem/sql/astute.sql
@@ -455,24 +455,26 @@ CREATE TABLE IF NOT EXISTS `invoice_detail` (
   CONSTRAINT `fk_InvDetail_InvNum` FOREIGN KEY (`inv_num`) REFERENCES `invoice` (`inv_no`) ON DELETE CASCADE ON UPDATE CASCADE
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
 
-CREATE DEFINER=`root`@`localhost` TRIGGER `astute`.`after_invoice_detail_update` AFTER UPDATE ON astute.invoice_detail FOR EACH ROW
+CREATE DEFINER=`root`@`localhost` TRIGGER `astute`.`after_invoice_detail_delete` AFTER DELETE ON astute.invoice_detail FOR EACH ROW
 BEGIN
     UPDATE invoice
-    SET bill_amt = (SELECT SUM(QTY*FEE) FROM invoice_detail WHERE invoice_detail.inv_num = OLD.inv_num);
+    SET bill_amt = (SELECT SUM(QTY*FEE) FROM invoice_detail WHERE invoice_detail.inv_num = OLD.inv_num) 
+    WHERE inv_no = OLD.inv_num;
 END;
 
 CREATE DEFINER=`root`@`localhost` TRIGGER `astute`.`after_invoice_detail_insert` AFTER INSERT ON astute.invoice_detail FOR EACH ROW
 BEGIN
     UPDATE invoice
-    SET bill_amt = (SELECT SUM(QTY*FEE) FROM invoice_detail WHERE invoice_detail.inv_num = NEW.inv_num);
+    SET bill_amt = (SELECT SUM(QTY*FEE) FROM invoice_detail WHERE invoice_detail.inv_num = NEW.inv_num)
+    WHERE inv_no = NEW.inv_num;
 END;
 
-CREATE DEFINER=`root`@`localhost` TRIGGER `astute`.`after_invoice_detail_delete` AFTER DELETE ON astute.invoice_detail FOR EACH ROW
+CREATE DEFINER=`root`@`localhost` TRIGGER `astute`.`after_invoice_detail_update` AFTER UPDATE ON astute.invoice_detail FOR EACH ROW
 BEGIN
     UPDATE invoice
-    SET bill_amt = (SELECT SUM(QTY*FEE) FROM invoice_detail WHERE invoice_detail.inv_num = OLD.inv_num);
+    SET bill_amt = (SELECT SUM(QTY*FEE) FROM invoice_detail WHERE invoice_detail.inv_num = OLD.inv_num)
+    WHERE inv_no = OLD.inv_num;
 END;
-
 	
 -- Dumping data for table astute.invoice_detail: ~14 rows (approximately)
 /*!40000 ALTER TABLE `invoice_detail` DISABLE KEYS */;