Adding more database constraints

db/build_db.js

@@ -91,7 +91,7 @@ conn.query('CREATE TABLE history(date DATETIME NOT NULL, reviewId INT NOT NULL,
 //
 
 conn.query('DROP TABLE IF EXISTS historyGroups');
-conn.query('CREATE TABLE historyGroups(categoryId INT NOT NULL, categoryValue FLOAT NOT NULL, historyId INT NOT NULL, FOREIGN KEY(historyId) REFERENCES history(id))');
+conn.query('CREATE TABLE historyGroups(categoryId INT NOT NULL, categoryValue FLOAT NOT NULL, historyId INT NOT NULL, FOREIGN KEY(historyId) REFERENCES history(id), FOREIGN KEY(categoryId) REFERENCES categories(id))');
 
 
 //

db/hscd.sql

@@ -77,7 +77,9 @@ CREATE TABLE `historyGroups` (
   `categoryValue` float NOT NULL,
   `historyId` int(11) NOT NULL,
   KEY `historyId` (`historyId`),
-  CONSTRAINT `historyGroups_ibfk_1` FOREIGN KEY (`historyId`) REFERENCES `history` (`id`)
+  KEY `categoryId` (`categoryId`),
+  CONSTRAINT `historyGroups_ibfk_1` FOREIGN KEY (`historyId`) REFERENCES `history` (`id`),
+  CONSTRAINT `historyGroups_ibfk_2` FOREIGN KEY (`categoryId`) REFERENCES `categories` (`id`)
 ) ENGINE=InnoDB DEFAULT CHARSET=latin1;
 /*!40101 SET character_set_client = @saved_cs_client */;
 
@@ -133,4 +135,4 @@ UNLOCK TABLES;
 /*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;
 /*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;
 
--- Dump completed on 2015-03-26 13:31:52
+-- Dump completed on 2015-04-18 13:51:01

server.go

@@ -185,17 +185,9 @@ func removeCategory(rw http.ResponseWriter, req *http.Request) {
 		return
 	}
 
-	result, err := db.Exec("DELETE FROM categories WHERE id = (?)", request.Id)
-	if err != nil {
-		log.Fatal(err)
-	}
+	_, err := db.Exec("DELETE FROM categories WHERE id = (?)", request.Id)
 
-	affectedRows, err := result.RowsAffected()
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	js, err := json.Marshal(jsonRemoveCategoryResponse{affectedRows > 0})
+	js, err := json.Marshal(jsonRemoveCategoryResponse{err == nil})
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -236,6 +228,17 @@ func accessReview(rw http.ResponseWriter, req *http.Request) {
 	}
 
 	for id, value := range request.Profile {
+		catRow := db.QueryRow("SELECT EXISTS(SELECT NULL FROM categories WHERE id = ?)", id)
+
+		var catExists int
+		if err := catRow.Scan(&catExists); err != nil {
+			log.Fatal(err)
+		}
+
+		if catExists == 0 {
+			continue
+		}
+
 		if _, err := db.Exec("INSERT INTO historyGroups(categoryId, categoryValue, historyId) VALUES(?, ?, ?)", id, value, insertId); err != nil {
 			log.Fatal(err)
 		}

static/scripts/profile.js

@@ -57,6 +57,9 @@
                     $(this).remove();
                 });
             }
+            else {
+                alert('Category could not be deleted because it is referenced by user access history.');
+            }
         }, 'json');
     }
 
@@ -69,9 +72,7 @@
         });
 
         $('#categories button').unbind().click(function() {
-            if (confirm('Are you sure you want to delete this category?')) {
             removeCategory(parseInt($(this).attr('data-categoryId')));
-            }
         });
     }