sqlクエリが実行時に印刷されます

Question

次のコードを実行すると、添付イメージの黄色で強調表示されたクエリがページに印刷されます。私はそのSQLを印刷したくありません。私のコードセグメントで何が間違っていますか？

if(isset($_REQUEST["stu_performance_activity_submit"])) 
    { 
    $stu_performance_main_category = $_REQUEST["stu_performance_main_category"]; 
    $stu_performance_sub_category = $_REQUEST["stu_performance_sub_category"]; 
    $stu_performance_activity_name = $_REQUEST["stu_performance_activity_name"]; 
    $stu_performance_activity_date = $_REQUEST["stu_performance_activity_date"]; 
    $stu_performance_activity_description = $_REQUEST["stu_performance_activity_description"]; 

    $newc = "INSERT INTO stu_performance_activity 
        (stu_performance_activity_id, 
        stu_performance_main_category, 
        stu_performance_sub_category, 
        stu_performance_activity_name, 
        stu_performance_activity_date, 
        stu_performance_activity_description) 
      VALUES ('', 
        '$stu_performance_main_category', 
        '$stu_performance_sub_category', 
        '$stu_performance_activity_name', 
        '$stu_performance_activity_date', 
        '$stu_performance_activity_description')"; 

    if($connection->query($newc) === TRUE) 
     { 

     } 
    else 
     { 
     echo "Error: " . $newc . "<br>" . $connection->error; 
     } 
    } 

Answer 1

プライマリキーは、INSERT中にNULLでなければなりません。

$newc = "INSERT INTO stu_performance_activity 
        (stu_performance_activity_id, 
        stu_performance_main_category, 
        stu_performance_sub_category, 
        stu_performance_activity_name, 
        stu_performance_activity_date, 
        stu_performance_activity_description) 
      VALUES (NULL, 
        '$stu_performance_main_category', 
        '$stu_performance_sub_category', 
        '$stu_performance_activity_name', 
        '$stu_performance_activity_date', 
        '$stu_performance_activity_description')";