I have this error Warning: mysqli num rows () expects parameter 1 to be mysqli result, boolean given

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I have this error Warning: mysqli num rows () expects parameter 1 to be mysqli result, boolean given

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#1 by (1 votes)

2

I have implemented a notification system, but I made a small addition to the connection and I get this error:

Warning: mysqli num rows() expects parameter 1 to be mysqli result, boolean given

But I do not know what it means or what I would like to suggest.

<?php
$conexion= mysqli_connect("localhost", "root", "", "antetodopopayan");
    $count = 0;
    $sql = "SELECT * FROM informacion WHERE estado = 0";
    $result = mysqli_query($conexion, $sql);
    $count = mysqli_num_rows($result);

if(!$conexion){
    echo "error";
}else{

}

?>

mysql php

asked by Stiven 24.12.2018 в 17:06

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1 answer

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score 1 · Accepted Answer

Well according to the comments area, you mention wanting to do an accountant for that query. so you should use an aggregation function like COUNT() given the above I propose that your code look like this:

<?php

$conexion = new mysqli("localhost", "root", "", "antetodopopayan");
$consulta = $conexion->query("SELECT COUNT(*) as T FROM informacion WHERE estado = 0");
$fila = $consulta->fetch_assoc();
echo $fila["T"];

OBSERVATIONS

As notes, best use an object-oriented style with new mysqli

As I'm going to count the rows that enter a condition, I put an alias to that same count, in this case T

In a variable $fila I assign the query to use the fetch_assoc() method

As a final step as I try to print the number of rows that enter given the condition in WHERE I do an echo of said variable, but accessing the key that I place that is T

UPDATE

If you want to manage the state of the connection then your code should look like this

<?php

$conexion = new mysqli("localhost", "root", "", "antetodopopayan");

if($conexion->connect_errno){
    return $conexion->connect_error;
}else{
    $consulta = $conexion->query("SELECT COUNT(*) as T FROM informacion WHERE estado = 0");
    $fila = $consulta->fetch_assoc();
    echo $fila["T"];
}