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Ricardo A
Asked: 2020-06-24 13:13:49 +0800 CST 2020-06-24 13:13:49 +0800 CST

PHP mysql_fetch_array

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I'm trying to display results from my database, I didn't know how until I saw this way of doing it while($row=mysql_fetch_array($result) { //Code }and then I saw that using this way is somewhat obsolete, so I would have to choose to use while($row = $query->fetch(PDO::FETCH_ASSOC)) { //Code }. My problem is that I don't understand how the while works: At what point does it stop being true? What is the data that it iterates? In a nutshell, how does this code work?

php

4 Answers

  1. Best Answer

    At what point does it stop being true? The while is a loop that as long as there are rows in the query will remain true once the query runs out of data the loop ends... it's very simple.

    What is the data that it iterates? It depends on what you request in your query; the index can be literal or numeric. and will read them by lines.

    How does this code work?

    while($row = $query->fetch(PDO::FETCH_ASSOC))
{#Mientrastenga registros devuelve true
    #lectura para la fila actual
    echo $row['indice Litera de columna'];
    echo '<br>'; #Salto de linea
}
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  2. The thing is:

    - while($row=mysql_fetch_array($result) {  //Code } =  forma procedural
- while($row = $query->fetch(PDO::FETCH_ASSOC)) { //Code } esto es POO

    That it would be the same while($row=mysql_fetch_assoc($result))in a procedural way

    What the does While, is that it executes as long as the condition is true.

    Greetings.

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  3. Well, basically what this line does:

    while($row = $query->fetch(PDO::FETCH_ASSOC)) { //Code }

    It is to return the data of each record that the query you made previously obtained.

    The While loop stops once the fetch stops sending data.

    You can access the data in the following way

    while($row = $query->fetch(PDO::FETCH_ASSOC)) {
//usa este si estas obteniendo los datos en forma de objeto 
echo $row->nombredelcampo;
//usa este si estas obteniendo los datos en una matriz
echo $row["nombredelcampo"];
 }

    Pd replace "fieldname" with the names of the fields you want to manipulate in your table.

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  4. In my opinion and criteria, the easiest way to query a table in the database is as follows:

    $connection = new PDO("mysql:host=localhost; dbname=database", "admin", "12345");
$connection -> setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$connection -> exec("SET CHARACTER SET utf8");

$age = 18;

$stmt = $connection -> prepare("SELECT * FROM USER WHERE AGE = :age");
$stmt -> bindParam(':age', $age);
$stmt -> execute();
$rows = $stmt -> fetchAll(PDO::FETCH_OBJ);
$stmt -> closeCursor();

foreach($rows as $user)
{
    echo $user -> NAME;
}

$connection = null;

    From the point of view of security and also from the point of view of using less code and being as efficient as possible. I hope that the code above is helpful, if you have any questions leave me a comment and I will gladly answer.

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