I have simple prepared statement, and i can't find solution to bind list of id's, so as you can see in first statement i get all ids that i need, and in next statement i need to put all those ids into IN clause, but i'm not able to do it, any suggestions how and what is best way to do it ?
$stmt = $mysqli->prepare("SELECT id FROM user WHERE groupId = ? ORDER BY id LIMIT ? OFFSET ?");
$stmt->bind_param("iii", $args['groupId'], $pageSize, $offset);
$stmt->execute();
$stmt->bind_result($id);
$userIds= array();
while ($stmt->fetch()) {
$userIds[] = $id;
}
$stmt= $mysqli->prepare("SELECT a.id as attendantId, a.firstName, a.lastName, c.id as caringId, c.startDate, c.endDate FROM attendant a LEFT JOIN caring c ON c.attendantId = a.id WHERE a.id IN (?)");
$stmt->bind_param('i', $userIds);
$stmt->bind_param('i', implode(',', $userIds));
Related
I am trying to do a multi query using prepared statements.
I am getting number of bind param errors :
Warning: mysqli_stmt::bind_param(): Number of variables doesn't match number of parameters in prepared statement in C:\wamp\www\c\index.php on line 35
Line 35 is:
$stmt->bind_param('i', $user_id);
Here is total codes:
I tried several examples but couldnt make it work.
Example 1:
$stmt->bind_param('i', $id); //output id from session
Example 2:
$stmt->bind_param('ii',$id, $user_id);
And some more tries too.
$id = $_SESSION['id']; // value comes from session and its full
$stmt = $mysqli->prepare("SELECT users.*, stores.*, products.* FROM stores, products, users WHERE users.id = ? AND stores.user_id = ? AND products.user_id = ?");
$stmt->bind_param('i', $user_id);
$stmt->execute();
$stmt->bind_result($id, $user_id, $pname);
$stmt->fetch();
$stmt->close();
echo $pname;
When I do queries in phpmyadmin codes works fine on $sql as following 2 queries:
$sql = "SELECT users.*, stores.*, products.*\n"
. "FROM stores, products, users\n"
. "WHERE ((users.id) AND (stores.user_id) AND (products.user_id))";
AND without php code
SELECT users.*, stores.*, products.*
FROM stores, products, users
WHERE ((users.id)
AND (stores.user_id)
AND (products.user_id))
This is the closest example :
I am having error:
Warning: mysqli_stmt::bind_result(): Number of bind variables doesn't match number of fields in prepared statement in C:\wamp\www\c\index.php on line 37
Line 37 is :
$stmt->bind_result($user_id, $username, $pname);
$id = $_SESSION['id'];
Closest code :
$stmt = $mysqli->prepare("SELECT users.*, stores.*, products.* FROM stores, products, users WHERE users.id = stores.user_id AND stores.user_id = products.user_id AND products.user_id = ?");
$stmt->bind_param('i', $id);
$stmt->execute();
$stmt->bind_result($user_id, $username, $pname);
$stmt->fetch();
$stmt->close();
echo $pname;
Your prepared statement contains 3 questionmarks/placeholder. So you have to bind exactly 3 values.
I think this should work:
$stmt = $mysqli->prepare("SELECT users.*, stores.*, products.* FROM stores, products, users WHERE users.id = ? AND stores.user_id = ? AND products.user_id = ?");
$stmt->bind_param('iii', $user_id, $user_id, $user_id);
See examples at: http://php.net/manual/de/mysqli-stmt.bind-param.php
Here is working sample of the code, I had to change:
SELECT users.*, stores.*, products.* FROM
To
SELECT users.id, users.username, stores.user_id, stores.name, products.user_id, products.pname FROM
And rest of the code like so: and its working now, I wouldlike to know if its safe to use on a live and dynamic website ?
Can someone correct the code please.
Here is total working code
$id = $_SESSION['UserId'];
$stmt = $mysqli->prepare("SELECT users.id, users.username, stores.user_id, stores.name, products.user_id, products.pname
FROM stores, products, users
WHERE users.id = ?
AND stores.user_id = users.id
AND products.user_id = users.id");
$stmt->bind_param('i', $id);
$stmt->execute();
$stmt->bind_result($id, $username, $user_id, $name, $user_id, $pname);
$stmt->fetch();
$stmt->close();
echo $pname;
echo"<br>" .$name;
echo "<br>".$username;
I tried INNER JOIN AND LEFT JOIN (Mentioned in comment) but couldnt made both. work
EDİT :
Same query with INNER JOIN its working.
$sid = $_SESSION['UserId'];
$stmt = $mysqli->prepare("SELECT u.id, u.username, s.user_id, s.name, p.user_id, p.pname FROM stores AS s INNER JOIN products AS p ON p.store_id = s.store_id INNER JOIN users AS u ON u.id = p.user_id WHERE s.user_id = ?");
$stmt->bind_param('i', $sid);
$stmt->execute();
$stmt->bind_result($id, $username, $user_id, $name, $user_id, $pname);
$stmt->fetch();
$stmt->close();
echo $pname;
echo"<br>" .$name;
echo "<br>".$username;
This is my code. I execute then nothing happen. Pls check my code
$id = trim(htmlentities($_REQUEST['id'],ENT_QUOTES)); //call the action from previous page
//fetch data
$stmt = $dbi->prepare("SELECT a.telco, a.no_siri, a.no_topup, a.amount, a.requestingAgentID, a.requestDateTime, a.isUsed, b.name FROM card_telco a LEFT JOIN agents b ON a.requestingAgentID = b.id WHERE id = ?"); //query
$stmt->bind_param('s', $id); //binding
mysqli_stmt_execute($stmt); //execute
mysqli_stmt_store_result($stmt); //store the result
$count = mysqli_stmt_num_rows($stmt); //execute rows
$stmt->bind_result($newTelco, $noSiri, $noTopup, $newAmount, $newRequestAgentID, $newRequestDateTime, $isUsing, $newName, $agendId); //binding new result
$stmt->execute() or die(mysqli_error()); //execute the statement
$stmt->store_result() //store new result
$stmt->fetch(); //fetch the data
$stmt->close(); //close the statement
ChromePhp::log('here'); //console
ChromePhp::log($newTelco, $noSiri); //console
Okay i got it!! My query is wrong.
SELECT a.id, a.telco, a.no_siri, a.no_topup, a.amount, a.requestingAgentID, a.requestDateTime, a.isUsed, b.name FROM card_telco a LEFT JOIN agents b ON a.requestingAgentID = b.id WHERE a.id = ?
This is my new query. Thanks for helping me
I am trying to select num1 and num2 from different users:
$stmt = $mysqli->prepare('SELECT `num1`, `num2` FROM `Mytable1` WHERE `user` in (SELECT DISTINCT `user` from `Mytable1` where type=2)');
$stmt->execute();
$stmt->bind_result($num1, $num2);
$stmt->store_result();
$stmt->fetch();
$stmt->close();
And I need get results $result = $num1 * $num2;
Then enter the result in Mytable2
$stmt = $mysqli->prepare('UPDATE `Mytable2` SET `num`=? WHERE `name` in (SELECT DISTINCT `user` FROM bookmaker_bets WHERE type=2)');
$stmt->bind_param('i', $result);
$stmt->execute();
$stmt->close();
How to make that num1 and num2 selected from each user, and not first user?
You can perform this update with one SQL statement:
UPDATE table2
INNER JOIN users ON users.userId = table2.userId
INNER JOIN table1 ON table1.userId = users.userId
SET table2.result = table1.num1 * table1.num2
WHERE users.type = 2;
Please, refer to this fiddle
The array showcasef holds 20 items per page. I do 3 different queries within the foreach loop, which is 60 queries (just for the loop, there's additional queries too).
<?php
foreach($showcasef as $itemf){
$sf_id = $itemf['sf_id'];
$sf_url = $itemf['sf_url'];
$sf_title = $itemf['sf_title'];
$sf_urltitle = post_slug($sf_title);
// Fetch number of favs
$stmt = $conn->prepare("SELECT COUNT(f_id) FROM favourites WHERE f_showcaseid=?");
$stmt->bind_param("i", $sf_id);
$stmt->execute();
$stmt->bind_result($numfFavs);
$stmt->fetch();
$stmt->close();
// Fetch class
$stmt = $conn->prepare("SELECT avg(r_class) FROM ranks WHERE r_showcaseid=?");
$stmt->bind_param("i", $sf_id);
$stmt->execute();
$stmt->bind_result($sf_class);
$stmt->fetch();
$stmt->close();
// Fetch number of classes
$stmt = $conn->prepare("SELECT COUNT(r_class) FROM ranks WHERE r_showcaseid=?");
$stmt->bind_param("i", $sf_id);
$stmt->execute();
$stmt->bind_result($numfClasses);
$stmt->fetch();
$stmt->close();
?>
Render HTML here
<?php } ?>
Will this be a severe performance issue, or are these particular queries relatively simple? If I keep the columns indexed, should it perform okay with millions of rows (potentially)? Or can the queries be optimized/simplified?
Here's how I get the showcasef:
$stmt = $conn->prepare("SELECT s_id,s_url,s_title FROM showcase WHERE s_userid=? ORDER BY s_date DESC LIMIT $skippingFactor, 20");
$stmt->bind_param("i", $u_id);
$stmt->execute();
$stmt->bind_result($sf_id,$sf_url,$sf_title);
while($stmt->fetch())
{
$showcasef[] = [
'sf_id' => $sf_id,
'sf_url' => $sf_url,
'sf_title' => $sf_title
];
}
$stmt->close();
A few suggestions here.
Reuse prepared statements
You are creating three prepared statements inside the loop. Why don't you create your statements only once, and then reuse them using multiple binds?
<?php
$stmt1 = $conn->prepare("SELECT COUNT(f_id) FROM favourites WHERE f_showcaseid=?");
$stmt1->bind_param("i", $sf_id);
$stmt1->bind_result($numfFavs);
$stmt2 = $conn->prepare("SELECT avg(r_class) FROM ranks WHERE r_showcaseid=?");
$stmt2->bind_param("i", $sf_id);
$stmt2->bind_result($sf_class);
$stmt3 = $conn->prepare("SELECT COUNT(r_class) FROM ranks WHERE r_showcaseid=?");
$stmt3->bind_param("i", $sf_id);
$stmt3->bind_result($numfClasses);
foreach($showcasef as $itemf) {
$sf_id = ...
$stmt1->execute();
$stmt1->fetch();
/* if the fetch succeedes then $numfFavs will contain the count */
$stmt2->execute();
...
$stmt3->execute();
..
}
$stmt1->close();
$stmt2->close();
$stmt3->close();
Use a single query to Count the rows and calculate the average
You can combine the second and third statement a single SQL query:
SELECT COUNT(r_class) AS cnt, AVG(r_class) AS average
FROM ranks
WHERE r_showcaseid=?
Use a single query instead a foreach loop
With the previous suggestions you can get better performances. But are you really sure you need a foreach loop?
If your IDs are returned by another query, instead of a foreach loop is better to use a subquery:
SELECT f_showcaseid, COUNT(f_id)
FROM favourites
WHERE f_showcaseid IN (SELECT id FROM ... WHERE ...)
GROUP BY f_showcaseid
or you can provide a list of IDs to the query:
SELECT f_showcaseid, COUNT(f_id)
FROM favourites
WHERE f_showcaseid IN (?,?,?,?,?)
GROUP BY f_showcaseid
(you can dynamically create the list of ? if the number of IDs is not fixed)
You could do this in a single query I think.
Something like the following:-
SELECT f_showcaseid, COUNT(f_id), avg(r_class), COUNT(r_class)
FROM ranks WHERE r_showcaseid IN (".implode(',', $showcasef).")
GROUP BY f_showcaseid
Of course, to use parameters you would need to do that a bit more elegantly:-
<?php
$stmt = $conn->prepare("SELECT f_showcaseid, COUNT(f_id), avg(r_class), COUNT(r_class)
FROM ranks WHERE r_showcaseid IN (".implode(',', str_split(str_repeat('?', count($showcasef)), 1)).")
GROUP BY f_showcaseid");
foreach($showcasef as $itemf)
{
$stmt->bind_param("i", $itemf['sf_id']);
}
$stmt->execute();
$stmt->bind_result($numfClasses);
$stmt->fetch();
$stmt->close();
?>
I have a query where I'm taking several results from a single table. I then need to loop through each result to get information from other tables, however, I can't get it to work.
Here's my code:
<?php
$type = 1;
if ($stmt = $cxn->prepare('SELECT username FROM users WHERE type = ?')) {
$stmt->bind_param('i', $type);
$stmt->execute();
$stmt->bind_result($username);
while ($stmt->fetch()) {
if ($stmt = $cxn->prepare('SELECT count FROM posts WHERE username = ?')) {
$stmt->bind_param('s', $username);
$stmt->execute();
$stmt->bind_result($result2);
$stmt->close();
}
}
$stmt->close();
}
?>
I get an error:
Call to a member function fetch() on a non-object
How do I fix this?
I would highly recommend a native SQL JOIN for this because it will avoid unnecessary overhead in sending potentially thousands of queries:
SELECT
u.username,
p.count
FROM
users u
LEFT JOIN // processed as LEFT OUTER JOIN so the syntax is interchangeable just fyi
posts p
ON u.username = p.username
WHERE
p.type = ?
Explaining LEFT JOIN only, we'll keep it simple =)
In the SQL above we start with username from the users table as a whole
users u just grants us the shortcut syntax for u.username so that SQL is readable and doesn't fubar
Next we want to attach the posts p table where u.username = p.username because we need the p.count for each username
Lastly we filter this conglomerate of data based on p.type being equal to something
Please note that are many things at play here depending on the DBMS. Such things include query optimizers, the exact point of filtering, etc... but that is far outside the scope of simply getting the hang of what we are trying to achieve conceptually so I will not go into detail because it will only cause confusion.
You are overwritting your stmt variable. You should use another one, like
$type = 1;
if ($stmt = $cxn->prepare('SELECT username FROM users WHERE type = ?')) {
$stmt->bind_param('i', $type);
$stmt->execute();
$stmt->bind_result($username);
while ($stmt->fetch()) {
if ($stmtCnt = $cxn->prepare('SELECT count FROM posts WHERE username = ?')) {
$stmtCnt->bind_param('s', $username);
$stmtCnt->execute();
$stmtCnt->bind_result($result2);
$stmtCnt->close();
}
}
$stmt->close();
}