我想检查一个id是否在用户表中注册在MySQL中,如果它在用户表中注册,则输入RFID并且如果不是echo无效id。到目前为止我已经这样做了,没有任何检查就进入了。这是tbl_attendance
,而ids在tbl_user
中注册。我从Arduino那里得到了自己的身份。
<?php
include ('connection.php');
$sql_insert = "INSERT INTO tbl_attendance (rfid_uid) VALUES ('".$_GET["rfid_uid"]."')";
if(mysqli_query($con,$sql_insert))
{
mysqli_close($con);
}
?>
答案 0 :(得分:-1)
此代码应该按照您的要求进行操作。您应该考虑使用预准备语句(例如PDO),因为不推荐使用mysqli库。
<?php
//Include the mysql connection to the database
include ('connection.php');
//Find the existing RFID rows
$result = mysqli_query($con, "SELECT id FROM tbl_user WHERE rfid_uid = '". $_GET["rfid_uid"] ."'");
//Count the number of rows
$count = mysqli_num_rows($result);
if( $count == 1 ){ //If the user exists in the tbl_usr
//Build the table insert query
$sql_insert = "INSERT INTO tbl_attendance (rfid_uid) VALUES ('".$_GET["rfid_uid"]."')";
//Execute that query
if( mysqli_query($con, $sql_insert) ){
echo "Attendance registered successfully!"; //Success message
} else {
echo "Attendance failed to register!"; //Failure message
}
} else {
//Display the "Invalid ID Message"
echo "Invalid id";
}
//Close the mysql connection object
mysqli_close($con);
?>