PHP, MySQL statement results in ZERO rows - php

hope someone can help me.
i have a very simple prepared SELECT statment in PHP:
$query_select = ("SELECT * FROM companies where user_name = ? ");
$stmt = $mysqli->prepare($query_select);
$stmt->bind_param("s", $user_name);
$stmt->execute();
$count = $stmt->num_rows;
in companies table I have several rows with the $user_name i`m trying to query. But i still get 0 rows as a result.
The strange thing is that the non PREPARED version works:
$query = 'SELECT * FROM companies WHERE user_name="'.$user_name.'"';
$result = $mysqli->query($query);
$count= $result->num_rows;
echo "Aantal: ".$count;
So my question is, does anyone know why the prepared version returns ZERO and the non prepared version returns the correct number of rows?

Add this line to your code between execute and num_rows statement.
$stmt->store_result();
You have to store it before counting it.

For mysqli prepared statements, you must take an additional step: storing the result.
Try this:
$query_select = ("SELECT * FROM companies where user_name = ? ");
$stmt = $mysqli->prepare($query_select);
$stmt->bind_param("s", $user_name);
$stmt->execute();
$stmt->store_result(); // <-- new line
$count = $stmt->num_rows;

May be you need to bind the result:
/* bind result variables */
$stmt->bind_result($district);
Full example here

Related

Count rows from an SQL statement and store in PHP variable [duplicate]

This question already has answers here:
Prepared Statements - Number of Rows
(4 answers)
Closed 1 year ago.
I have the following SQL code in my PHP file. I want to count the number of rows returned and store it in a variable so I can output it on the page.
I've tried a few solutions I found but none of them worked.
$stmt = $con->prepare('SELECT id, owner_id, hs_name, hs_address FROM hotspots WHERE owner_id = ?');
$stmt->bind_param('i', $_SESSION['id']);
$stmt->execute();
$stmt->bind_result($hsid, $ownerid, $hsname, $hsaddress);
while($stmt->fetch()) {
// print results in loop
}
Any help would be much appreciated.
I fixed this by adding
$stmt->store_result();
$count = $stmt->num_rows;
After the execute, so the entire thing now looks like
$stmt = $con->prepare('SELECT id, owner_id, hs_name, hs_address FROM hotspots WHERE owner_id = ?');
$stmt->bind_param('i', $_SESSION['id']);
$stmt->execute();
$stmt->store_result();
$count = $stmt->num_rows;
$stmt->bind_result($hsid, $ownerid, $hsname, $hsaddress);
MySQLi provides a nice way of doing this, you can simply use the num_rows property on the statement after it has been executed. This will immediately return the number of rows returned by the statement.
$stmt->execute();
$count = $stmt->num_rows;

why iam getting an error related to bind_result in error_log file and how to fix it? [duplicate]

This question already has answers here:
mysqli_stmt::bind_result(): Number of bind variables doesn't match number of fields in prepared statement
(2 answers)
Closed 1 year ago.
Iam getting this error
[07-Sep-2017 11:48:47 UTC] PHP Warning: mysqli_stmt::bind_result():
Number of bind variables doesn't match number of fields in prepared
statement
$stmt = $con->prepare("SELECT * FROM table where Id =?");
$stmt->bind_param("s", $_POST['Id']);
$stmt->execute();
$result = $stmt-> bind_result($Id);
$numRows = $result->num_rows;
if($numRows > 0) {
if($row = $result->fetch_assoc())
{
$Taxname=$row['TaxName'];
$Tid=$row['Id'];
}}
You need to alter your query. Instead of * you need to instead opt for picking out the data you actually want from the database.
For example, if the table table has columns Id,TaxName then you would execute like so:
<?php
$sqlData = array();
$stmt = $con->prepare("SELECT Id,TaxName FROM table where Id =?");
$stmt->bind_param("i", $_POST['Id']); //id is an integer? this should be i instead of s
$stmt->execute();
$stmt->store_result(); //store the result, you missed this
$stmt-> bind_result($Id,$TaxName); //bind_result grabs the results and stores in a variable
$numRows = $stmt->num_rows; //see the correction I made here
if($numRows >0){
while ($stmt->fetch()) { //propper way of looping thru the result set
$sqlData [] = array($Id,$TaxName);
//assoc array would look like:
//$sqlData [] = array("Id" =>$Id,"TaxName" => $TaxName);
}
}
$stmt->close(); //close the connection
?>
Then you would have an array of results that you can use after you've finished with mysqli queries.
Hope this helps you understand it a bit more.
$stmt = $con->prepare("SELECT Id,TaxName FROM table where Id =?");
$stmt->bind_param("s", $_POST['Id']);
$stmt->execute();
$result = $stmt-> bind_result($Id,$TaxName);
$stmt->store_result();
$numRows = $stmt->num_rows;
if($numRows > 0) {
while( $result->fetch_assoc())
{
$newid = $Id;
$newtaxname= $TaxName;
}
print_r($newid)."<br>";
print_r($newtaxname);
}
This code will give you the answer without any warnings.
Reference : http://php.net/manual/en/mysqli-stmt.bind-result.php
mysqli_stmt::bind_result — Binds variables to a prepared statement for
result storage

MSSQL php pdo pagination, some thing wrong on bindParam

Working fine with MsSQL:
$ppage = 15;
$poset = 0;
$stmt = "SELECT * FROM tbl ORDER BY ID OFFSET {:$poset } ROWS FETCH NEXT {:ppage } ROWS ONLY";
$stmt = $this->conn->prepare($stmt);
$stmt->execute();
return $row = $stmt->fetchAll();
Not working fine with MsSQL:
$ppage = 15;
$poset = 0;
$stmt = "SELECT * FROM tbl ORDER BY ID OFFSET :poffset ROWS FETCH NEXT :perpage ROWS ONLY";
$stmt = $this->conn->prepare($stmt);
$stmt->bindParam(':poffset', $poset);
$stmt->bindParam(':perpage', $ppage);
$stmt->execute();
return $row = $stmt->fetchAll();
the query is fine with I use to run with variables actual data it works but it's not working when I set the variable by bindParam, when am I missing.
thanks in advance.
Try using bindValue instead:
$stmt = $this->conn->prepare($stmt);
$stmt->bindValue(':poffset', $poset, PDO::PARAM_INT);
$stmt->bindValue(':perpage', $ppage, PDO::PARAM_INT);
$stmt->execute();
Rather than using the bindParam() function, inside of the parameters of the execute() function, add an array containing the values.
Something like this:
$stmt = $this->conn->prepare($stmt);
$stmt->execute(array(':poffset' => $poset, ':perpage' => $ppage)); // using an array rather than the bindValue function.
Use it as you would normally with the bindParam function, but substitute the commas for =>.
This way of doing things will save you having to call the bindParam() function for each value & will still protect against SQL Injection.

Anything wrong with this MySQL query?

$stmt = $connection->prepare("SELECT id FROM articles WHERE position =? LIMIT 1");
$stmt-> bind_param('i',$call );
$stmt->execute();
$result = $stmt->fetch();
$oldpostid = $result;
$stmt->close();
I don't see anything wrong with it, but it is returning 1 or nothing. $call is set and integer. I tried this too:
$stmt = $connection->prepare("SELECT * FROM articles WHERE position =? LIMIT 1");
$oldpostid = $result['id'];
Assuming this is all working you need to bind the result variables as well. mysqli_stmt_fetch returns a boolean:
$stmt->execute();
$stmt->bind_result($id);
$stmt->fetch();
$oldpostid = $id;
You seem to be mixing mysqli & PDO. The first line is PDO
$stmt = $connection->prepare("SELECT id FROM articles WHERE position =? LIMIT 1");
The next line is mysqli
$stmt-> bind_param('i',$call );
Should be for PDO the unnamed variables in place holder Manual Example 4
$stmt-> bindParam(1,$call );
$stmt->execute();
OR using array
$stmt->execute(array($call));

Writing this MySQLi query as a prepared statement

I have an existing MySQLi query:
$conn = dbConnect('query');
$galNumb = "SELECT COUNT(pj_gallery_id) FROM pj_galleries WHERE project = {$project}";
$gNumb = $conn->query($galNumb);
$row = $gNumb->fetch_row();
$galTotal = $row[0];
This counts the number of galleries per project that match the value in the query string contained in $project.
It works perfect but is not secure compared to a prepared statement. I have been researching this for two days and can not learn how to write this statement as a prepared statement. Any and all help will be insanely appreciated.
UPDATE:
I am flying by the seat of my pants here. I simply need to be shown how to code the above as a prepared statement. This sort of thing isn't resonating with my brain like learning PHP did and I'm just not getting any of this. The PHP manual is confusing and seems to be written for people who already understand PHP.
In short, I need a prepared statement version of the above code so that I can echo the result on the page. Currently, with what is in my DB, the number should be 3, and it consistently returns 1.
I wish I knew more so that I could better phrase my questions, but alas, I'm still learning. My apologies.
UPDATE 2:
Based on suggestions and research, I have this query written, but it ALWAYS returns the value 1, regardless of what's actually in the database:
$galNumb = "SELECT COUNT(pj_gallery_id) FROM pj_galleries WHERE project_part = ?";
$stmt = $conn->prepare($galNumb);
$stmt->bind_param('i', $project);
$gNumb = $stmt->execute();
Again, All I want to do is COUNT how many galleries are in each project. I know this should be simple but it isn't for me. There is currently 1 project in the DB with 3 galleries. The query should return 3.
This is as simple as it gets. This will prepare a sql statement, execute it and fetch the first row.
<?php
// create the prepared statement
$stmt = $conn->prepare('SELECT COUNT(pj_gallery_id) FROM pj_galleries WHERE project = ?');
// bind a variable to the statment
// the character denotes the type of the variable
// 's' for string
// 'i' for integer
$stmt->bind_param('i', $project);
// execute the query
$stmt->execute();
// get the result variable
$result = $stmt->get_result();
// fetch the row
$row = $result->fetch_row();
if ($row) {
echo "The count is " . $row[0];
}
?>
The documentation is pretty straightforward. You have a code example at the bottom.
http://php.net/manual/en/mysqli.prepare.php
$stmt = $dbConnection->prepare('SELECT COUNT(pj_gallery_id) FROM pj_galleries WHERE project = ?');
$stmt->bind_param('s', $project);
$stmt->execute();

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