I have a simple SQL Query:
$stmt = $db_main->prepare("SELECT id FROM user WHERE username=? AND mail=? LIMIT 1");
$stmt->bind_param('ss', $username, $mail);
$stmt->execute();
And I want to know, if it found an user. So I want to count the rows found.
I already tried to use rowCount (Not safe for SELECT) or num_rows or just looking if the result id is numeric (Which '' would not be, I hoped...)
There has to be an easy way to count the selected row, hasn't be?
Check number of rows returned with:
$stmt->num_rows;
Check for instance this site.
p.s.: added as per question in comment: use fetch() in order to get the next record.
...
$stmt->execute();
$stmt->bind_result($user_id); // access id
$stmt->store_result(); // optional: buffering (see below)
if ($data = $stmt->fetch()) {
do {
print("Id: " . $user_id);
} while ($data = $stmt->fetch());
} else {
echo 'No records found.';
}
Regarding store_result() from the documentation:
"You must call mysqli_stmt_store_result() for every query ..., if and only if you want to buffer the complete result set by the client ..."
Related
I'm trying to get the last 3 records from my table + only the titles column but I get only one result.
$query = $connect->prepare("SELECT title FROM tutorials LIMIT 3");
$query->execute();
$result = $query->fetch(PDO::FETCH_ASSOC);
foreach($result as $key => $value) { echo $value; }
Is working if I use fetchAll but in my case I don't need all the columns, just the only one(title) so there is no sense using fetchall but why is returning only one row?
fetch retrieves one row, or it returns FALSE if there is no row to fetch. (We could do the processing in a loop, and fetch each "next row", until fetch returns FALSE.
$query->execute();
while ( $row = $query->fetch(PDO::FETCH_ASSOC) ) {
echo $row['title'];
}
There's only one column in the resultset. It seems like we are confused about fetch and fetchAll.
http://php.net/manual/en/pdostatement.fetch.php
http://php.net/manual/en/pdostatement.fetchall.php
If we use fetchAll to retrieve all of the rows, we get an array back, each element in the array is a row from the resultset.
$query->execute();
if( $rs = $query->fetchAll(PDO::FETCH_ASSOC) ) {
foreach($rs as $row) {
echo $row['title'];
}
}
http://php.net/manual/en/pdostatement.fetch.php says:
PDOStatement::fetch — Fetches the next row from a result set
It only fetches one row each time you call fetch(). You either need to call it in a loop until it reaches the end of your result set, or else use fetchAll().
It sounds like you are mixing up the terms "row" and "column" somehow.
Hi I follow the OTRS developer manual for using sql queries inside the modules.
I run the following query but I only get first value from result.
my $SQL = "SELECT id FROM roles ";
$Self->{DBObject}->Prepare(SQL => $SQL, Limit => 15);
my #Row = $Self->{DBObject}->FetchrowArray();
if I check the size of #Row array I get one but in reality I have many roles created in roles table.
Can some one tell me whats missing ?
I can't add the code snippet in the comment to the other answer but here goes;
FetchrowArray() will return a list of columns for one row of the result, so you'd have to iterate over it like below; as pointed out. And if you want to add all results to an array, just use push.
$Self->{DBObject}->Prepare(
SQL => "SELECT id FROM table",
Limit => 10
);
my #IDs;
while ( my #Row = $Self->{DBObject}->FetchrowArray() ) {
push #IDs, $Row[0];
}
FetchrowArray() should be in a loop. This is an example from the OTRS doc:
$DBObject->Prepare(
SQL => "SELECT id, name FROM table",
Limit => 10
);
while (my #Row = $DBObject->FetchrowArray()) {
print "$Row[0]:$Row[1]\n";
}
I believe you should use SelectAll instead. SelectAll() return an array reference, not an array.
Basically, I have a mysql database where every time I get a row, I want to delete it from the database (after reading its information).
I know I could do something like
$result = mysql_query(" SELECT <some row> FROM table ");
$row = mysql_fetch_array($result);
$id = $row["id"];
mysqli_query(" DELETE FROM table WHERE id=$id");
but now it seems I have two queries going on. Is there a command to tell mysql that I want the row deleted as soon as it gives me the information? I imagine that'd save time and resources.
In my head, it looks like
$result = mysql_query(" SELECT <some row> FROM table THEN DELETE ");
EDIT additional information: I wish to use the SELECTed information after deleting the row. To put it simply, I only want one instance of the information to exist at any give time; it would be as if I were only "moving" a physical copy of the information, so that when it is put on a device/what have you, it is no longer in the table since there is only one copy.
Sorry if my understanding of mysql is rough -- I'm pretty new to it :P
I don't know why you need it but you can use a stored procedure for that:
DELIMITER $$
CREATE PROCEDURE select_and_delete(IN aid INT)
BEGIN
SELECT * FROM table1 WHERE id = aid;
DELETE FROM table1 WHERE id = aid;
END$$
DELIMITER ;
Here is SQLFiddle demo.
mysql_* extension is deprecated, therefore use prepared statements and mysqli or PDO.
Your php code using PDO might look like
$id = 1;
try {
$db = new PDO('mysql:host=localhost;dbname=test;charset=UTF8', 'user', 'userpwd');
$db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$db->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
$query = $db->prepare("CALL select_and_delete(?)");
$query->execute(array($id));
$result = $query->fetchAll(PDO::FETCH_ASSOC);
} catch (PDOException $e) {
echo "Exception: " .$e->getMessage();
$result = false;
}
$query = null;
$db = null;
//do whatever you need to do with your resultset
var_dump($result);
Following a rather simplified table structure (with the only column id) presented in SQL Fiddle example if you call it with $id=1 you'll you'll get in $result:
array(1) {
[0]=>
array(1) {
["id"]=>
int(1)
}
}
You'll need to add a timestamp field (with default as CURRENT_TIMESTAMP) to be able to tell when the row was added.
Then you can run the following MySQL query.
DELETE FROM `table` WHERE `timestamp` > DATE_SUB(NOW(), INTERVAL 0 SECOND);
You will need to run this as a cron job though. AFAIK it can't be done in MySQL alone.
i keep having this error "mysql_fetch_array() expects parameter 1 to be resource, null given in" when i try to display the returned value of count in sql. heres my code.
$query="SELECT med_rec_ID, COUNT(med_rec_ID)
FROM med_issue
WHERE MONTH(issue_date) = MONTH('2013-02-05')
GROUP BY med_rec_ID";
$result= mysql_query($query);
while($count = mysql_fetch_array($display3)){
echo $count[0];
}
i have tried to run the query in sql alone it displays 2 columns (the med_rec_ID, and the COUNT). guys how do i display the count and fix the error too?
First of all, don't use mysql_* functions since they're deprecated. Use mysqli or PDO.
Secondly, look at what you're passing into the fetch_array function.
You probably want to do something like:
$link = mysqli_connect("localhost", "admin", "pass", "db_name");
$result = mysqli_query($link, $sql);
while($row = $result->fetch_array(MYSQLI_ASSOC)){
$medIds[] = $row['med_rec_ID'];
...
}
Then fix the count by giving it an alias.
Please note that you should actually store how you access the DB in a more secure manner, but I use this only to illustrate the example. Here's a pretty good post: How to create global configuration file?
Is your query even executing? that error will happen if mysql_query doesnt return the resource, in case query fails
$query="SELECT med_rec_ID, COUNT(med_rec_ID) as C FROM med_issue where MONTH(issue_date) = MONTH('2013-02-05') GROUP BY med_rec_ID";
$result= mysql_query($query) or die(mysql_error());
while($row = mysql_fetch_assoc($result))
{
echo $row["C"];
}
Note: Please do not use mysql_* functions anymore
Give it an alias:
SELECT
med_rec_ID,
COUNT(med_rec_ID) TheCount
FROM med_issue
where MONTH(issue_date) = MONTH('2013-02-05') GROUP BY med_rec_ID
then you can select that column TheCount inside the while loop with $row['TheCount'], also use lope through the $result:
$result = mysql_query($query);
while($row = mysql_fetch_array($result)){
echo $row['TheCount'];
}
I'm trying to retrieve content using two items in the URL. Here is the php/symfony code that should do it:
$em = $this->getDoctrine()->getEntityManager();
$repository = $this->getDoctrine()
->getRepository('ShoutMainBundle:Content');
$query = $repository->createQueryBuilder('p')
->where('p.slug > :slug')
->andWhere('p.subtocontentid > :parent')
->setParameters(array(
'slug' => $slug,
'parent' => $page
))
->getQuery();
$content = $query->getSingleResult();
However, when this code is executed it returns the following error:
No result was found for query although at least one row was expected.
I have done some tests, and the data held in the $slug and $page variables hold the correct information. I have also tested the MySQL query and the query brings up the desired result, which confuses me further.
Have I missed something?
As it was answered here
You are getting this error because you are using the
getSingleResult() method. it generates an Exception if it can't find
even a single result. you can use the getOneOrNullResult() instead
to get a NULL if there isn't any result from the query.
Query#getSingleResult(): Retrieves a single object. If the result
contains more than one object, an NonUniqueResultException is thrown.
If the result contains no objects, an NoResultException is thrown. The
pure/mixed distinction does not apply.
No result was found for query although at least one row was expected.
Another reason could be:
You did this
$query = $this->getEntityManager()
->createQuery('
SELECT u FROM MyBundle:User u
WHERE u.email = :email')
->setParameter('email', $email);
return $query->getSingleResult();
Instead of this
$query = $this->getEntityManager()
->createQuery('
SELECT u FROM MyBundle:User u
WHERE u.email = :email')
->setParameter('email', $email);
$query->setMaxResults(1);
return $query->getResult();
Don't you want to use "=" instead of ">" ?
If you've got this message because used
$content = $query->getSingleResult();
you can just replace it with the row below
$content = $query->getOneOrNullResult(AbstractQuery::HYDRATE_SINGLE_SCALAR) ?? 0;