PHP error while getting multiple rows - php

I am trying to get all rows in database. My code:
$sql = "SELECT * FROM lectors";
$array = array();
while($row = mysqli_fetch_assoc(mysqli_query($con,$sql))){
echo $row["name"];
}
While I send request, server doesn't reply. Any ideas?

while($row = mysqli_fetch_assoc(mysqli_query($con,$sql))){
This is a never ending loop, your query will execute fine every time and loop will never terminate.
Need I say further?
It is only as good as
while(true)
{
// keep querying my database until i run out of resources
}
Execute the query first and loop over its result only.
And Oh,
While I send request, server doesn't reply
Because, as i said; It is busy running in a circle, has no time to reply.

Try to put the query in a line by itself, such as...
$sql = "SELECT * FROM lectors";
$array = array();
$res = mysqli_query($con,$sql);
while($row = mysqli_fetch_assoc($res)){
echo $row["name"];
}
Doing it in the method you are above will result in each execution of the loop executing the database query.

Related

php statement for multiple users not working

I am helping in some PHP design for a friends text game and have come to a stump.
I have scheduled a cron job to call the following page / following code, which is working correctly
<?php require("connect.php"); ?>
<?php
$sql = "SELECT id, name, health FROM users";
$query = mysql_query($sql) or die(mysql_error());
$row = mysql_fetch_object($query);
while($row = mysql_fetch_object($query)) {
$id = htmlspecialchars($row->id);
$name = htmlspecialchars($row->name);
$health = htmlspecialchars($row->health);
$sql = "SELECT * FROM property WHERE living='1' AND ownerid='$id'";
$query = mysql_query($sql) or die(mysql_error());
$row = mysql_fetch_object($query);
while($row = mysql_fetch_object($query)) {
$OwnerName = htmlspecialchars($row->ownername);
$OwnerID = htmlspecialchars($row->ownerid);
$RaidPropBonus = htmlspecialchars($row->raidperc);
$RaidPropMoney = htmlspecialchars($row->raidcash);
$PropertyLvl = htmlspecialchars($row->proplvl);
$Living = htmlspecialchars($row->living);
if($PropertyLvl == '5' && $Living == '1'){
if($health < '100'){
$result = mysql_query("UPDATE users SET health=$health + '1' WHERE id='$id'")
or die(mysql_error());
} else { }
} else { }
}
}
?>
Although this only works for ONE user only. I cannot understand why this is. Any other logged in / out accounts that have met the criteria have been ignored. I can maybe only think I am missing a loop? As the ID that is being met first is number 1 and it has stopped there?
Anybody advice at all maybe?
UPDATE - It seems correct I need to get a loop in there, but am so far failing to get this loop working correct. No matter where I seem to amend / add a loop it does not help. Please may somebody suggest anything?
UPDATE2 - As requested, updated with the new version of loop
For what I've understood, the loops should be made on the mysql_fetch_object that will get the each row from the query.
Take a look at the snippet
<?php
require("connect.php");
// here prepare the $userQuery (the one that fetches all users)
// then the first loop that will read each usew row
// AFAICT this should afect all script
while($userRow = mysql_fetch_object($userQuery))
{
// prepare data fetched from the $userQuery
// prepare the $propertyQuery (the one that fetches all properties of the user)
// then the second loop to read all user property rows
// and this will afect the updates
while($propertyRow = mysql_fetch_object($propertyQuery))
{
// prepare data fetched from $propertyQuery
// add logic here
}
}
?>
Also #Matthew Carpenter had a valid point, that mysql_* is deprecated, you should consider in using mysqli_*, or in my opinion take a look at PDO

php request of mysql query timeout

i'm trying to make a long mysql query and process and update the row founded:
$query = 'SELECT tvshows.id_show, tvshows.actors FROM tvshows where tvshows.actors is not NULL';
$result = mysql_query($query);
$total = mysql_num_rows($result);
echo $total;
while ($db_row = mysql_fetch_assoc($result))
{
//process row
}
but after 60 second give me a timeout request, i have try to insert these in my php code:
set_time_limit(400);
but it's the same, how i can do?
EDIT:
only the query:
$query = 'SELECT tvshows.id_show, tvshows.actors FROM tvshows where tvshows.actors is not NULL';
takes 2-3 second to perform, so i think the problem is when in php i iterate all the result to insert to row or update it, so i think the problem is in the php, how i can change the timeout?
EDIT:
here is the complete code, i don't think is a problem here in the code...
$query = 'SELECT tvshows.id_show, tvshows.actors FROM tvshows where tvshows.actors is not NULL';
$result = mysql_query($query);
$total = mysql_num_rows($result);
echo $total;
while ($db_row = mysql_fetch_assoc($result)) {
//print $db_row['id_show']."-".$db_row['actors']."<BR>";
$explode = explode("|", $db_row['actors']);
foreach ($explode as $value) {
if ($value != "") {
$checkactor = mysql_query(sprintf("SELECT id_actor,name FROM actors WHERE name = '%s'",mysql_real_escape_string($value))) or die(mysql_error());
if (mysql_num_rows($checkactor) != 0) {
$actorrow = mysql_fetch_row($checkactor);
$checkrole = mysql_query(sprintf("SELECT id_show,id_actor FROM actor_role WHERE id_show = %d AND id_actor = %d",$db_row['id_show'],$actorrow[0])) or die(mysql_error());
if (mysql_num_rows($checkrole) == 0) {
$insertactorrole = mysql_query(sprintf("INSERT INTO actor_role (id_show, id_actor) VALUES (%d, %d)",$db_row['id_show'],$actorrow[0])) or die(mysql_error());
}
} else {
$insertactor = mysql_query(sprintf("INSERT INTO actors (name) VALUES ('%s')",mysql_real_escape_string($value))) or die(mysql_error());
$insertactorrole = mysql_query(sprintf("INSERT INTO actor_role (id_show, id_actor, role) VALUES (%d, %d,'')",$db_row['id_show'],mysql_insert_id())) or die(mysql_error());
}
}
}
}
Should definitely try what #rid suggested, and to execute the query on the server and see the results/duration to debug - if the query is not a simple one, construct it as you would in your PHP script, and only echo the SQL command, don't have to execute it, and just copy that in to the server MySQL command line or whichever tool you use.
If you have shell access, use the top command after running the above script again, and see if the MySQL demon server is spiking in resources to see if it really is the cause.
Can you also try a simpler query in place of the longer one? Like just a simple SELECT count(*) FROM tvshows and see if that also takes a long time to return a value?
Hope these suggestions help.
There are so many problems with your code.
Don't store multiple values in a single column. Your actors column is pipe-delimited text. This is a big no-no.
Use JOINs instead of additional queries. You can (or could, if the above weren't true) get all of this data in a single query.
All of your code can be done in a single query on the server. As I see it, it takes no input from the user and produces no output. It just updates a table. Why do this in PHP? Learn about INSERT...SELECT....
Here are some resources to get you started (from Googling, but hopefully they'll be good enough):
http://www.sitepoint.com/understanding-sql-joins-mysql-database/
http://dev.mysql.com/doc/refman/5.1/en/join.html
http://dev.mysql.com/doc/refman/5.1/en/insert-select.html
What is Normalisation (or Normalization)?
Let me know if you have any further questions.

How to perform a function for every row in a mysql array?

UPDATE: I solved it using a for loop:
for ($i=0; $i < mysql_num_rows($result); $i++) {
$row = mysql_fetch_assoc($result);
echo $row['name'];
}
ORIGINAL QUESTION:
This looks kinda stupid. I'm sure im missing something that's very simple, since I was able to accomplish this before. Anyways, I want to echo some text for every item in an array. This array is derived from mySQL.
here's the code
while ($row = mysql_fetch_assoc(mysql_query("SELECT * FROM files"))) {
echo $row['name'];
}
can you post the complete code? I think you forgot the database connection.
Try this:
$result = mysql_query("SELECT * FROM files") or die (mysql_error());
while ($row = mysql_fetch_assoc($result)) {
var_dump($row['name']);
}
This will throw an error, I guess you made a mistake over there. Also, var_dump() your $row in the while to make 100% sure you have "a" value.
Also, are you sure the row does exist? If don't have any records, the echo on your $row will not work sinc it does not exist.
Also, set error reporting to E_ALL like so.
error_reporting(E_ALL);
Also, since you are running your query inside the while() loop, it will continue to run forever. So first run the query, and put it in a variable, and then loop through the results. (see my piece of code above)
You can execute query individual instead of while loop because if your query return more than 1 rows it will goes under the loop. show your loop print only first data of result and your loop is infinite.
From your question it seems so simple, try this way it's working.
$sql="SELECT name From files";
$names = $db->query($sql);
while($name1 = $db->fetchByAssoc($names))
{
echo $name1['name'];
}

mysql_fetch_array() timing out

I am trying to query a database, but it seems to just load for an age and not do anything. It's a simple query and shouldnt take longer than a millisecond.
while($row = mysql_fetch_array(getWallPosts($userid)))
{
}
Now when I replace this code with:
echo mysql_num_rows(getWallPosts($userid));
It just displays '1' in fact there's only one record in the DB and it's just a simple SELECT statement.
Here's the getWallPosts function:
function getWallPosts($userid, $limit = "10")
{
$result = dbquery("SELECT * FROM commentpost
WHERE userID = ".$userid."
ORDER BY commentPostID DESC LIMIT 0, ".$limit);
return $result;
}
Also, when I put the SQL string that it's executing into MySQL's query browser. It takes no time at all.
Any ideas?
You appear to be looping indefinitely because you're retrieving a new set (one record) of data each time.
$result = getWallPosts($userid);
while ($row = mysql_fetch_array($result)) {
//printf($row[0]);
}
You need to get the data once and loop through it. Your code is getting the data, running the loop and then getting the data again.
Try:
$posts = getWallPosts($userid);
while($row = mysql_fetch_array($posts))
{
//Code to execute
}
Its an infinite loop. The expression in the while always executes so it will always be true.
You're returning a new result set each time the while statement executes. You should call getWallPosts first, assign it to $results, and then loop over it.

PHP question regarding a while statement for a loop

I asked someone to code up a loop for me, although I asked for the loop to run constantly as it should be doing checks. Say I wanted it to run for 2 hours in a loop.
They created this;
$result = select_query ('tbltest', 'id,userid,test');
while ($data = mysql_fetch_array ($result))
{
$userid = $data['userid'];
$id = $data['id'];
$test = $data['test'];
}
I don't know much about PHP, but it seems to me that once there are no more rows to go through and place in an array, it will end the loop.
How can I go about fetching the rows, but continuing in a loop for the next 2 hours?
Thanks!
I have no idea why you want to continue looping for 2 hours and doing nothing, but here's a solution (albeit a stupid one, if it serves your purpose):
set_time_limit(0);
$time = time();
while (time()<$time+7200)
{
if ($data = mysql_fetch_array ($result))
{
$userid = $data['userid'];
$id = $data['id'];
$test = $data['test'];
}
sleep(1); // so PHP doesn't consume too much resources
}
If you want to check something for a set amount of time, you should setup a cronjob to run a PHP script every X minutes rather than have a PHP script looping continuously.
you can't. when you do the select_query it actually returns a pointer of the full resultset as of that moment. the $data = mysql_fetch_array ($result) can only iterate over that values that were present in the resultset at the time of the initial select_query ('tbltest', 'id,userid,test');
call.. not to mention that I can't think of any properly configured PHP server that's going to let you leave a script running for 2 hours without timing out. perhaps what you want is a front-page with a AJAX script that re-checks the database for you in a loop. so that you would have your $.GET, and on the successfull return of your data you'd fire off another $.GET...
Can't you put the original database query inside stillstanding's loop?
set_time_limit(0);
$time = time();
while (time()<$time+7200)
{
$result = select_query ('tbltest', 'id,userid,test');
if ($data = mysql_fetch_array ($result))
{
$userid = $data['userid'];
$id = $data['id'];
$test = $data['test'];
}
sleep(1); // so PHP doesn't consume too much resources
}

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