PHP通过ajax插入MySQL数据类型错误

Question

我已经通过ajax插入了数据并且插入了数据但给出了错误[错误:

INSERT INTO jobify_user (u_name,u_phonenumber,u_email,u_password) VALUES 

('','','','')

[1]Incorrect integer value: '' for column 'u_phonenumber' at row 1]

$sql = "INSERT INTO jobify_user (u_name,u_phonenumber,u_email,u_password)

  VALUES ('$username','$userphonenumber','$useremail','$userpassword')";

   if ($conn->query($sql) === TRUE) {

   echo "New record created successfully";

   } else {

     echo "Error: " . $sql . "<br>" . $conn->error;

   }

Answer 1

$sql = "INSERT INTO jobify_user (u_name,u_phonenumber,u_email,u_password)

  VALUES ('".$username."','".$userphonenumber."','".$useremail."','".$userpassword."')";

   if ($conn->query($sql) === TRUE) {

   echo "New record created successfully";

   } else {

     echo "Error: " . $sql . "<br>" . $conn->error;

   }