i'm new in PDO and now i'm facing this
Uncaught Error: Unsupported operand types
in mysql_ (old way) it work just fine to set to divide limit with rows, but it won't work with PDO,
this is the old way
limit is 4 start from 0, the database is more than 100 to count, the logic just fine
$query=mysql_query("SELECT * FROM `articles` LIMIT $start, $limit");
$rows=mysql_num_rows(mysql_query("SELECT * FROM `articles`"));
$total=ceil($rows/$limit);
and with the PDO (new way they said)
$query=$db -> query("SELECT * FROM `articles` LIMIT $start, $limit");
$rows=$query->fetch(PDO::FETCH_ASSOC);
$total=ceil($rows/$limit);
and i get the error msg, any clues?
In your mysql_-example you are explicitly fetching the rowcount of a query.
In your PDO implementation you are only fetching one result from the resultset your query returned. You could do something like this:
$query = $db->query("SELECT * FROM `articles` LIMIT $start, $limit");
$rows = $query->fetchAll(PDO::FETCH_ASSOC);
$total = ceil(count($rows)/$limit);
edit: If it is only about counting the rows you should to so in the db.
$query = $db->query("SELECT count(*) AS rowcount FROM `articles` LIMIT $start, $limit");
$rows = $query->fetch(PDO::FETCH_ASSOC);
$total = ceil($rows['rowcount']/$limit);
i have a question which is my limit statement didn't work i want the content select from database and limit the show content in 40 only but it didn't work
here is my SQL statement with php code
$chatroomID=$_GET['chatroomID'];
$userID = $_SESSION['id'];
$sql="SELECT * FROM chatroom_chat WHERE chatroom_id ='$chatroomID'";
$result1 = mysqli_query($connection, $sql) or die(mysqli_error($connection));
while ($row = mysqli_fetch_array($result1)) {
$chat = $row['chat_id'];
$sql3 ="SELECT * FROM (
SELECT * FROM chat WHERE id = '$chat' ORDER BY id DESC LIMIT 0,40
) sub
ORDER BY id ASC ";
$getChatData = mysqli_query($connection,$sql3) or die(mysqli_error($connection));
/*here have statement to get username*/
while($row3 = mysqli_fetch_array($getChatData)) {
echo "<div>all content</div>";
}
}
does my code have any syntax error? i no sure why it didn't work
SELECT * FROM (
SELECT * FROM chat WHERE id = '$chat' ORDER BY id DESC LIMIT 40
) sub
ORDER BY id ASC
I have 2 database tables. loppe containing username and loppeID, and billeder containing loppeID and billedeNavn.
I would like to have a div containing 2 random billedeNavn from the same username. I have tried some things but I can only figure out how to get 2 billedeNavn from the same loppeID (username). I'm pretty new to all this. So would me grateful for any help.
<?php
$frontimage = ("SELECT * FROM loppe RIGHT JOIN billeder ON loppe.loppeID=billeder.loppeID WHERE loppe.username = '$username' ORDER BY RAND()");
$st = $db->prepare($frontimage);
$st->execute();
$row = $st->fetch();
$loppeid = $row['loppeID'];
$loppe = $loppeid;
$sql = "SELECT * FROM billeder WHERE loppeID = :loppeID order by rand() limit 2";
$stmt = $db->prepare($sql);
$stmt->execute(array("loppeID" => $loppe));
while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
$fname = $row['billedeNavn'];
echo '<div class="col-xs-6 loppe-pic-outer"><img class="img-responsive loppe-pic" src="loppebilleder/'.$fname.'"></div>';
}
?>
Have you tried this change your
$sql = "SELECT * FROM billeder WHERE loppeID = :loppeID order by rand() limit 2";?
to this
$sql = "SELECT * FROM billeder WHERE loppeID = '.$loppeid.' order by rand() limit 2";
A good way to figure out what is going on when using php and database is after you create your query do something like
$sql = "SELECT * FROM billeder WHERE loppeID = '.$loppeid.' order by rand() limit 2";
die($sql);
So with this you will see what the database is really querying and you can check for in your sql string or query.
I wonder... is this possible to select a random row in my DB where only the record that contains field->Status = 0 ? because i only need a row that contains 0 in the field name=Status. if the status contains = 1 , then the row will not belong in the randomization.
my code in the query is
$result = mysql_query( " SELECT * FROM `$haha` ORDER BY RAND() limit 1");<br>
$result = mysql_query( " SELECT * FROM `$haha` ORDER BY RAND() limit 1 Where Status=0");
But it does not work.. i appreciate your replies.. thank you very much!
Try below code:
$result = mysql_query("SELECT * FROM `".$haha."` Where Status=0 ORDER BY RAND() limit 0,1");
Your where clause should be before then the order by clause.
And want to know what is the value of $haha.
You use the wrong syntax. The good one:
$result = mysql_query( " SELECT * FROM `$haha` Where Status=0 ORDER BY RAND() limit 1");
I'm not sure exactly how to explain what the query does, however the problem isn't entirely with how it's set up, because it does work, in another instance, when I use it as an array, however it's not working when I use it with mysql_fetch_assoc(), so here is what my original query is(not the one im having trouble with):
SELECT * FROM
(SELECT * FROM comments
WHERE postID='$id' AND state='0'
ORDER BY id DESC LIMIT 3
) t ORDER BY id ASC
what this does is selects the last 3 comments on a post, then orders them in another way (so they show up in the correct order, old to new) Now this is the query for echoing out the array of comments directly.
But now what I want to do, is to just get the first id out of the 3 comments.
here's what I have tried to do (and by the way, this query DOES work, when i replace my previous query to echo out the results in an array, but i need to get just the id for use, i don't want an array):
$previousIDq = mysql_fetch_assoc(mysql_query("
SELECT * FROM
(SELECT * FROM comments
WHERE postID='$id' AND state='0'
ORDER BY id DESC LIMIT 3
) t ORDER BY id ASC LIMIT 1"));
$previousID = $previousIDq['id']; //this doesn't return the id as I want it to.
Your problem may be that there are no matching rows.
Also, I think you could also improve your query to this:
SELECT * FROM comments WHERE postID='$id' AND state='0' ORDER BY id DESC LIMIT 2,1
But as others say, use PDO or MySQLi, and with prepared statements. And don't SELECT * ever.
try a var_dump($previousID) to see what you get
It is probably giving you back an object, and you need to get your id from that object
You script is too condensened for error handling, let alone debugging
$mysql = mysql_connect(...
$query = "
SELECT * FROM
(SELECT * FROM comments
WHERE postID='$id' AND state='0'
ORDER BY id DESC LIMIT 3
) t ORDER BY id ASC LIMIT 1
";
$result = mysql_query($query, $mysql);
if ( !$result ) { // query failed
die('<pre>'.htmlspecialchars(mysql_error($mysql)).'</pre><pre>'.htmlspecialchars($query).'</pre>');
}
$previousIDq = mysql_fetch_assoc($result);
if ( !$previousIDq ) {
die('empty result set');
}
else {
$previousID = $previousIDq['id'];
}
You need to separate your code to be able to debug
$query = "SELECT * FROM
(SELECT * FROM comments
WHERE postID='$id' AND state='0'
ORDER BY id DESC LIMIT 3
) t ORDER BY id ASC LIMIT 1";
$result = mysql_query($query);
echo mysql_error(); //what eror comes out here
while($previousIDq = mysql_fetch_assoc($result))
{
print ($previousIDq['id']);
}
NOTE: mysql_* is depreciated, upgrade to mysqli or PDO
Please stop using mysql_ functions to write new code, it is being deprecated. Use mysqli_ or PDO functions (mysqli below).
Bind your parameters to prevent SQL injection
Always use a column list (don't use SELECT *)
If you're returning > 1 row, use a while loop
mysqli_ solution
$link = mysqli_connect("localhost", "user_name", "password", "stock");
if (mysqli_connect_error()) {
die('Connect Error (' . mysqli_connect_errno() . ') ' . mysqli_connect_error());
}
$stmt = mysqli_prepare($link, "SELECT t.id FROM
(SELECT id FROM comments
WHERE postID = ? AND state = 0
ORDER BY id DESC
LIMIT 3) t
ORDER BY id ASC");
mysqli_bind_param($stmt, 's', $id) or die(mysqli_error($dbh));
$result = mysqli_stmt_execute($stmt) or die(mysqli_error($link));
while($row = mysqli_fetch_assoc($result)) {
echo $row[id];
}
mysqli_close($link);
mysql_ solution
$stmt = "SELECT t.id FROM
(SELECT id FROM comments
WHERE postID = $id AND state = 0
ORDER BY id DESC
LIMIT 3) t
ORDER BY id ASC";
$result = mysql_query($stmt) or die(mysql_error());
$row = mysql_fetch_assoc($result);
while($row = mysql_fetch_assoc($result)) {
echo $row[id];
}