Mysql Queries Error Inside a While Loop - php

I have a while loop from a query called $result.
Inside this while loop I have two other queries $anchors1 and $anchors2
The first one retrieves the first 2 rows;
The second one should retrieve the following ones using an offset.
For some reason the queries seem to interact one another, not displaying the 3 row and pulling a duplicate row which should not be there.
Is there any way this queries would interfere?
If I delete the first one, the second query works. Same vice versa.
The platform is Wordpress.
while($slice = mysql_fetch_assoc($result)){
$i++;
if($enable_position1 == 'y' && $i == $position[0]):
$anchors1 = mysql_query("SELECT * FROM anchors WHERE site_url = '$site_current' LIMIT 3");
while($anc = mysql_fetch_assoc($anchors)){
$site_anchor = $anc['site_anchor'];
$site_current = $anc['site_current'];
echo '<li>'.$site_anchor.'</li>';
}
elseif($enable_position2 == 'y' && $i == $position[1]):
$anchors2 = mysql_query("SELECT * FROM anchors WHERE site_url = '$site_current' LIMIT 999 OFFSET 3");
while($anc2 = mysql_fetch_assoc($anchors2)){
$site_anchor2 = $anc2['site_anchor'];
$site_current2 = $anc2['site_current'];
echo '<li>'.$site_anchor2.'</li>';
}
else:
the_post();
endif;
}
Ty very much!

In the second query, you're using the variable $site_current, which is set in the first query's block. Depending on how your application is designed, that could be causing the interference. I think you meant to put $site_current2 there.

Related

How to get Fetch_array data

I am making Tournament mod. And I do not know how to correctly do some operations with fetched array.
What my code is doing, is that it takes data from Tournament table and add it to array. Then print it in HTML table, so all users can see the place where he has.
How can I correctly get the first, second, third array data for the first 3 winners and give them a price? And how can I deal with players who have the same amount of points?
Right now the query below seems to not work too, all statements are positiv and it should execute the function.
if($counter == 1) {
$GLOBALS['DATABASE']->query("UPDATE ".USERS." SET `atm` = `atm` + 20000 WHERE `id` = ".$recordRow['id_owner']." ;");
}
Sorry, my English is not good and I tried to search for the answers but didn't find anything, because i do not know for what PHP solution should i search.
My code:
$recordFetch = $GLOBALS['DATABASE']->query("SELECT *FROM `uni1_tournament` ORDER BY wons DESC;");
$counter = 0;
$RangeList = array();
while ($recordRow = $GLOBALS['DATABASE']->fetch_array($recordFetch)) {
$counter += 1;
$RangeList[] = array(
'id' => $recordRow['id_owner'],
'name' => $recordRow['name'],
'points' => $recordRow['wons']*5,
'counter' => $counter,
);
if($t_time > TIMESTAMP) {
if($counter == 1) {
$GLOBALS['DATABASE']->query("UPDATE ".USERS." SET `atm` = `atm` + 20000 WHERE `id` = ".$recordRow['id_owner']." ;");
}
elseif($counter == 2) {
//to do;
} elseif($counter == 3) {
//to do;
}
}
}
Make query like this "select * from uni1_tournament GROUP BY points ORDER BY
points desc limit 3";
If you're using regular mysql or mysqli (been a while since I have for either, moved to doctrine a while back), fetch_array needs to be ran on the results and not the GLOBALS['DATABASE'] variable (guessing this a global variable for the database connection).
Try changing
while ($recordRow = $GLOBALS['DATABASE']->fetch_array($recordFetch)) {
to
while ($recordRow = $recordFetch->fetch_array()) {
In order to use your original formatting, I believe fetch_array needed to be mysqli_fetch_array instead.
i.e
while ($recordRow = $GLOBALS['DATABASE']->mysqli_fetch_array($recordFetch)) {

How to display two while loop variables

I am trying to display multiple columns with multiple rows from a database. It works to display one row, but when I put in the second one it just displays two of the same. Like an echo. How do I get it to display the two different numbers?
$result = mysql_query("SELECT plea, COUNT(plea) as cee FROM tee WHERE section='d' GROUP BY
plea" , $c) or die("two");
$number=mysql_num_rows($result);
if($number>0)
{
$i=0;
while($row_result = mysql_fetch_array($result))
{
$plea.$i = $row_result['plea'];
$cee.$i = $row_result['cee'];
echo $plea.$i." ".$cee.$i."<br><br>";
$i++;
}
}
This is VERY strange code:
$plea.$i = $row_result['plea'];
and NOT doing what you want. It's parsed as:
$plea . ($i = $row_result['plea']);
and boils down to $i getting your value from the query, and then being further executed down to just
TRUE
without EVER modifying the value in $plea. You probably want an array:
$plea[$i] = $row_result['plea'];

How do I get the first and last results from a query?

I am creating a pagination script and I need to get the first and last results in the database query so that I can determine what results appear when the user clicks a page to go to. This is the code that I have at the minute:
// my database connection is opened
// this gets all of the entries in the database
$q = mysql_query("SELECT * FROM my_table ORDER BY id ASC");
$count = mysql_num_rows($q);
// this is how many results I want to display
$max = 2;
// this determines how many pages there will be
$pages = round($count/$max,0);
// this is where I think my script goes wrong
// I want to get the last result of the first page
// or the first result of the previous page
// so the query can start where the last query left off
// I've tried a few different things to get this script to work
// but I think that I need to get the first or last result of the previous page
// but I don't know how to.
$get = $_GET['p'];
$pn = $_GET['pn'];
$pq = mysql_query("SELECT * FROM my_table ORDER BY id ASC LIMIT $max OFFSET $get");
// my query results appear
if(!$pn) {
$pn = 1;
}
echo "</table><br />
Page $pn of $pages<br />";
for($p = 1;$p<=$pages;$p++) {
echo "<a href='javascript:void(0);' onclick='nextPage($max, $p);' title='Page $p'>Page $p</a> ";
}
I think you have few problems there, but I try to tackle them for you. First, as comments say above, you are using code that it vulnerable to SQL injection. Take care of that - you might want to use PDO, which is as easy use as MySQL extension, and will save you from many trouble (like injection).
But to your code, lets go through it:
You should ask DB to get count of the rows, not using mysql function, it's far more effective, so use SELECT count(*) FROM mytable.
For $pages use ceil() as you want all rows to be printed, if you have $max 5 and have 11 rows, round will make $pages 2, where you actually want 3 (last page just contains that last 11th row)
in LIMIT you want to LIMIT row_count OFFSET offset. You can calculate offset from page number, so: $max = row_count but $offset = ($max * $page) - $max. In your code if $get is directly the page, it means you get $get'th row (Not sure though what happens in your JS nextpage. Bare in mind that not all use JavaScript.)
I have prepared simple example here which uses PDO, maybe that gives you idea how simple it's use PDO.
The selecting rows shows example how to put parameters in SQL, it would be perfectly safe in this case state, 'SELECT * FROM pseudorows LIMIT '.$start.','.$max by I wanted to make an example how easy it is (and then safe):
// DB config
$DB_NAME = 'test';
$DB_USER = 'test';
$DB_PASSWD = 'test';
// make connection
try {
$DB_CONN = new PDO("mysql:host=localhost;dbname=".$DB_NAME, $DB_USER, $DB_PASSWD);
$DB_CONN->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch (PDOException $e) {
die($e);
}
// lets say user param 'p' is page, we cast it int, just to be safe
$page = (int) (isset($_GET['p'])?$_GET['p']:1);
// max rows in page
$max = 20;
// first select count of all rows in the table
$stmt = $DB_CONN->prepare('SELECT count(*) FROM pseudorows');
$stmt->execute();
if($value = $stmt->fetch()) {
// now we know how many pages we must print in pagination
// it's $value/$max = pages
$pages = ceil($value[0]/$max);
// now let's print this page results, we are on $page page
// we start from position max_rows_in_page * page_we_are_in - max_rows_in_page
// (as first page is 1 not 0, and rows in DB start from 0 when LIMITing)
$start = ($page * $max) - $max;
$stmt = $DB_CONN->prepare('SELECT * FROM pseudorows LIMIT :start,:max');
$stmt->bindParam(':start',$start,PDO::PARAM_INT);
$stmt->bindParam(':max', $max,PDO::PARAM_INT);
$stmt->execute();
// simply just print rows
echo '<table>';
while($row = $stmt->fetch()) {
echo '<tr><td>#'.$row['id'].'</td><td>'.$row['title'].'</td></tr>';
}
echo '</table>';
// let's show pagination
for($i=1;$i<=$pages;$i++) {
echo '[ '.$i.' ]';
}
}
mysql_fetch_array returns an associative array
Which means you can use reset and end to get the first and last results:
$pqa = mysql_fetch_array($pq);
$first = reset($pqa);
$last = end($pqa);
I don't see how you plan to use the actual results, just page numbers should be sufficient for pagination.
Still, hope it helps. And yes, upgrade to mysqli, so your code doesn't get obsolete.

php query does not retrieve any data?

well, i wanna pull out some data from a mysql view, but the wuery dos not seem to retrieve anything ( even though the view has data in it).
here is the code i've been "playing" with ( i'm using adodb for php)
$get_teachers=$db->Execute("select * from lecturer ");
//$array=array();
//fill array with teacher for each lesson
for($j=0;$j<$get_teachers->fetchrow();++$j){
/*$row2 = $get_lessons->fetchrow();
$row3=$row2[0];
$teach=array(array());
//array_push($teach, $row3);
$teach[$j]=mysql_fetch_array( $get_teachers, TYPE );
//echo $row3;*/
$row = $get_teachers->fetchrow();
//$name=$row[0]+" "+$row[0]+"/n";
//array_push($teach, $row1);
echo $row[0]; echo " ";echo $row[1]." ";
//$db->debug = true;
}
if i try something like "select name,surname from users", the query partially works . By partially i mean , while there are 2 users in the database, the loop only prints the last user.
the original query i wanted to execute was this
$get_teachers=$db->Execute("select surname,name from users,assigned_to,lessons
where users.UID=assigned_to.UID and lessons.LID=assigned_to.LID and
lessons.term='".$_GET['term']."'");
but because it didnt seem to do anything i tried with a view ( when you execute this in the phpmyadmin it works fine(by replacing the GET part with a number from 1 to 7 )
the tables in case you wonder are: users,assigned_to and lessons. ( assigned_to is a table connecting each user to a lesson he teaches by containing UID=userid and LID=lessonid ). What i wanted to do here is get the name+surname of the users who teach a lesson. Imagine a list tha displays each lesson+who teaches it based on the term that lesson is available.
Looking at http://adodb.sourceforge.net/ I can see an example on the first page on how to use the library:
$rs = $DB->Execute("select * from table where key=123");
while ($array = $rs->FetchRow()) {
print_r($array);
}
So, you should use:
while ($row = $get_teachers->fetchrow()) {
instead of:
for ($j = 0; $j < $get_teachers->fetchrow(); ++$j) {
The idea with FetchRow() is that it returns the next row in the sequence. It does not return the number of the last row, so you shouldn't use it as a condition in a for loop. You should call it every time you need the next row in the sequence, and, when there are no more rows, it will return false.
Also, take a look at the documentation for FetchRow().
for($j=0;$j<$get_teachers->fetchrow();++$j){
... a few lines later ...
$row = $get_teachers->fetchrow();
See how you call fetchrow() twice before actually printing anything? You remove two rows from the result set for every 1 you actually use.
while ($row = $get_teachers->fetchrow()) {
instead and don't call fetchrow() again within the loop.
Because you're fetching twice first in the loop
for($j=0;$j<$get_teachers->fetchrow();++$j){
... some code ...
// And here you fetch again
$row = $get_teachers->fetchrow();
You should use it like this
while ($row = $get_teachers->fetchrow()) {

SQL Result Random loop through

I have a SQL database that contains a field. I can get all of the elements in that field by:
$result=mysql_query($sql);
while($row=mysql_fetch_array($result)){
$ftype =$row['ftype']; //name of field is 'ftype'
print $ftype} //do something
I want a random element to be printed out each time the page is opened/refreshed.
Knowing that the result is an array containing the information i want, I want to randomly choose an element of the array. Also, if there are N elements in the array, I want to choose all N elements exactly once before I show any element again for second time. The process repeats itself. I know how to code something like this in java or python, but I don't think that's the way I should go.
I think I need to use javascript, but I'm just not sure what technology to use.
UPDATE:
Patrick's idea seems to be exactly what i was looking for. I thought I would share what I have now and maybe you can suggest optimization. I hope the intent in the code is obvious.
<?
session_start();
if (!isset($_SESSION['count']) || !isset($_SESSION['randomArray'])) {
$count = 0;
$randomArray = array();
$sql="SELECT youtubeurl FROM Foodlist";
$result=mysql_query($sql);
while($row=mysql_fetch_array($result)){
array_push($randomArray,$row['youtubeurl']);
}
shuffle($randomArray);
$_SESSION['randomArray'] = $randomArray;
$_SESSION['count'] = $count;
} elseif ($_SESSION['count'] >= sizeof($_SESSION['randomArray'])){
$_SESSION['count'] = 0;
$randomArray = $_SESSION['randomArray'];
shuffle($randomArray);
$_SESSION['randomArray'] = $randomArray;
} else{
$randomArray = $_SESSION['randomArray'];
$count = $_SESSION['count'];
echo $randomArray[$count];
$_SESSION['count']++;
}
?>
You can do this without Javascript, however you'll need to open/maintain a session.
Pseudocode:
data = data_from_mysql()
choice = random.choice(data, exclude = SESSION['choices'])
SESSION['choices'].append(choice)
print choice
if len(SESSION['choices']) == len(data):
SESSION['choices'] = []
If you want a random result let the dbms take care of it. Add this to the bottom of your sql query.
ORDER BY RAND()
LIMIT 1

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