I'm new to PHP and SQL. I'm trying to make a rule so that it will only show certain information for certain pages. The code I'm using is
include 'dbh-login.php';
$id = $_GET['id'];
$i = 1;
while ($i != 100) {
$sql = "SELECT * FROM ui_off WHERE id='$i'";
$result = mysqli_query($conn, $sql);
$row = mysqli_fetch_assoc($result);
if ($row['link'] = $id) {
echo $row['title']."<br>";
}
$i++;
}
The if statement seems to have no effect on weather the script echoes the title or not.
You are missing == assignment. Here is the working code.
$id = $_GET['id'];
$i = 1;
while ($i != 100) {
$sql = "SELECT * FROM ui_off WHERE id='$i'";
$result = mysqli_query($conn, $sql);
$row = mysqli_fetch_assoc($result);
if ($row['link'] == $id) {
echo $row['title']."<br>";
}
$i++;
}
Your code does not make any sense.
You are using a while loop and looping in it 100 times just to check if 1 row have the given id.
Why don't you search directly for the id? Your code will be cleaner and you will free some memory on the server by deducting 100 queries each time the page is opened.
$id = $_GET['id'];
$sql = "SELECT * FROM ui_off WHERE id!='100' AND link='$id'" ;
$result = mysqli_query($conn, $sql);
$row = mysqli_fetch_assoc($result);
if ($row['link'] != '') {
echo $row['title']."<br>";
}
Related
i have two button on my homepage one is time-in and the other is time-out,
i want to prevent the user/student to time-in using same id if he did not put time-out on his last time-in to create valid entry. Hope you can help me.
here is my php code:
<?php
include_once('connection.php');
if(isset($_POST['submit0'])){
$rfid = $_POST['rfid'];
$time=date("H:i:s");
$sql = mysqli_query($conn, "SELECT * FROM stud WHERE rfid_num = '$rfid'");
$count = mysqli_num_rows($sql);
if ($count == 0 ) {
header("location:notexist.php");
} elseif (empty($row['timeout'])) {
header("location:page say the user/student need to put timeout first before time-in again");
} else {
while( $row = mysqli_fetch_array($sql)) {
$rfid=$row['rfid_num'];
$id=$row['id'];
$name0 = $row['name'];
$course0 = $row['course'];
$image = $row['image'];
$InsertSql = "INSERT INTO student_att(rfid_num,id,name,course,image,timein) VALUES ('$rfid','$id','$name0','$course0','$image','$time')";
$res = mysqli_query($conn, $InsertSql);
}
}
}
?>
this is my answer just wanna share it, i just add select student_att table
to fetch the data and check if timeout column is empty.
<?php
include_once('connection.php');
if(isset($_POST['submit0'])){
$rfid = $_POST['rfid'];
$time=date("H:i:s");
$sql = mysqli_query($conn,"select * from stud where rfid_num ='$rfid' ");
$count = mysqli_num_rows($sql);
if ($count == 0) {
header("location:notexist.php");
}else{
while( $row = mysqli_fetch_array($sql)) {
$rfid=$row['rfid_num'];
$id=$row['id'];
$name0 = $row['name'];
$course0 = $row['course'];
$image = $row['image'];
$sql1 = mysqli_query($conn,"select * from student_att where rfid_num ='$rfid' order by number DESC limit 1 ");
while( $row = mysqli_fetch_array($sql1)) {
if(empty($row['timeout'])){
header("location:logout.php");
}else{
$InsertSql = "INSERT INTO student_att(rfid_num,id,name,course,image,timein) VALUES ('$rfid','$id','$name0','$course0','$image','$time')";
$res = mysqli_query($conn, $InsertSql);
}
}
}
}
}
?>
Hi i have two arrays built by using mysql_fetch_array() i want to use them both in one while loop :
$username =$_SESSION["username"];
$password =$_SESSION["password"];
$query1= "SELECT * FROM subs WHERE username='$username' AND password='$password' ";
$res1 = mysql_query($query1);
$row_cnt1 = mysql_num_rows($res1);
if($res1 === FALSE) {
die(mysql_error()); // TODO: better error handling
}
$row1 = mysql_fetch_array($res1);
if($row_cnt1 == 1){
$sid = $row1["id"];
}else{
die("there is more than one user with the same username and password");
}
$query2= "SELECT * FROM bookreservations ";
$res2 = mysql_query($query2);
$row_cnt2 = mysql_num_rows($res2);
if($res2 === FALSE) {
die(mysql_error()); // TODO: better error handling
}
$row2 = mysql_fetch_array($res2) ;
$query= "SELECT * FROM books";
$res = mysql_query($query);
$row_cnt = mysql_num_rows($res);
if($res === FALSE) {
die(mysql_error()); // TODO: better error handling
}
while ($row = mysql_fetch_array($res)){
if($row2["sid"] == $sid && $row2["bid"] == $row["id"]){
continue;
}
$temp = $row["id"];
$temp1 = $row["title"];
echo "Title : ".$temp1."<br><br>";
$temp1 = $row["authors"];
echo "Authors : ".$temp1."<br><br>";
$temp1 = $row["copies"];
echo "Copies : ".$temp1."<br><br><br><br>";
echo "<div class=\"re\"><input type=\"radio\" value=\"reserve\" name=\"".$temp ."\">reserve</div> <br><br><br><br><br><br>" ;
}
I want to extract things from row array but i don't want them to have some values from row2 array so I have to use them both in one while loop ,THE SUMMARY row array is ok it jumps to the next row in each loop but row2 array is stuck it doesn't move to the next row what to do ?
Although I don't really understand your task well, I however, would recommend the following edits
My assumption: You are trying to fetch all rows from $res for each $res2.
Although inefficient technique, but I'll edit your code as below.
while($row2 = mysql_fetch_array($res2) ){
while ( $row = mysql_fetch_array($res) ){ //Both $row & $row2 will have equal incremented rows.
}
}//Outer loop
I am trying to show the points outside whileloop. I am fetching result like this.
Facebook
Twitter,Facebook,Instagram,Youtube
Facebook
Facebook
It fetches Facebook from each row and count no of times in the end.
<?php
$q = "select * FROM users";
$r = mysql_query($q);
$total = mysql_num_rows($r);
while($row = mysql_fetch_assoc($r)) {
$fb= $row['social'];
$dbreq = implode(',',explode(',', $fb));
$fa=array("Twitter,",",Instagram,","Youtube");
$newstring = str_replace($fa, "", $dbreq);
echo $points= count(explode(',', $newstring));
}
?>
Please try like this,
<?php
$q = "select * FROM users";
$r = mysql_query($q);
$total = mysql_num_rows($r);
$cnt =0 ;
while($row = mysql_fetch_assoc($r)) {
$fb= $row['social'];
if (strpos($fb,'facebook') !== false) {
$cnt++;
}
}
echo "TOTAL:".$cnt;
?>
I am in the process of learning mysqli and I am trying to query a databases and return multiple rows. I understand that a loop has to be used to return multiple rows but I have no idea how I would implement this into my code. Some help in doing this would be greatly appreciated.
$query2 = mysqli_query($con,"SELECT * FROM journeys WHERE id = $id");
$count = mysqli_num_rows($query2);
if ($count == 0) {
$journeys = 'You have no future journeys.';
} else {
while ( $row = mysqli_fetch_assoc($query2) ) {
$from = $row ['origin'];
$to = $row ['destination'];
$date = $row ['date'];
$hour = $row ['hour'];
$minute = $row ['minute'];
$journeyid = $row ['journeyid'];
try this code
<?php
$con= mysqli_connect('localhost', 'root', '', 'your data base name');
$query2 = mysqli_query($con,"SELECT * FROM journeys where id=$id");
$count = mysqli_num_rows($query2);
if ($count == 0) {
$journeys = 'You have no future journeys.';
echo $journeys;
} else {
while ( $row = mysqli_fetch_assoc($query2) ) {
$from = $row ['origin'];
$to = $row ['destination'];
$date = $row ['date'];
$hour = $row ['our'];
$minute = $row ['minute'];
$journeyid =$row ['journeyid'];
echo $from.'<br>';
}
}
have a look at this line echo $from; this will display what ever you have in the origin column in your database, if you want to display destination, use this as well echo $to;
means what ever you want to display do it like this echo $variableName; it will display the result;
before you display the result it will only store it, but will not display it,
have a look i change your this line of code as well
its your code
if ($count == 0) {
$journeys = 'You have no future journeys.';
echo $journeys;// i added this line
i added one line, because what you are saying here that if $count is equal to zero, than $journeys='you have no future journeys'; but you are not using echo you have to use echo to display the result.
if you still have some confusion ask again, and try to google as well
$query2 = mysqli_query($con,"SELECT * FROM journeys WHERE id = $id");
$row = mysql_fetch_array($query2);
$count = count($row);
if(intval($count)>0)
{
for($i = 0; $i<$count; $i++)
{
$from[$i] = $row[$i]['origin'];
-------------------------------
----------------------
}
}
I am executing a query like this (PHP + MySQL):
$query = "SELECT * FROM tablename WHERE 1";
$result = mysql_query($query);
while($row = mysql_fetch_array($result))
{
// PHP Statement
}
I want to use the same result again on the same page then i need to execute query again like this:
$query = "SELECT * FROM tablename WHERE 1";
$result = mysql_query($query);
while($row = mysql_fetch_array($result))
{
// PHP Code
}
then it works. But if I use only
while($row = mysql_fetch_array($result))
{
// PHP Code
}
Then it doesn't work. Is there any other way to use the result many times on the same page without executing query every time?
I know i can use the same result to make an array. but is there any other way?
I believe mysql_data_seek will do this for you.
<?php
function mysql_pointer_position($result_set) {
$num_rows = mysql_num_rows($result_set);
$i = 0;
while($result = mysql_fetch_array($result_set)) {
$i++;
}
$pointer_position = $num_rows - $i;
//Return pointer to original position
if($pointer_position <= $num_rows - 1) {
mysql_data_seek($result_set, $pointer_position);
}
return $pointer_position;
}
?>