Connecting PHP to the Mysql database

Question

I need help I am trying to connect my PHP file with the database to be able to perform a query and present on the screen the records.

Connection code:

define('usuario_bd', 'root');
define('senha_bd', '');
define('nome_bd', 'loja');

mysql_connect('localhost/phpmyadmin', usuario_bd, senha_bd);
mysql_select_db(nome_bd);

$pesquisa = "SELECT * FROM nome";
$querybd = mysql_query($pesquisa);

while($correto = mysql_fetch_array($querybd)){
        echo $correto["nome"];
}

My server is Wampserver connection with phpMyAdmin.

Answer 1

The Phpmyadmin nay is a database and mysql nay connects via HTTP, mysql itself is already a proper TCP protocol.

Mysql and Phpmyadmin difference

read this:

• What’s the difference between Mysql and phpMyAdmin?
• Difference between mysql_connect() and mysqli_connect() functions in php

Don’t use the old API

The functions that begins with mysql_ in the prefix are Old API, read this:

• Why should we not use mysql type functions_*?

How to use the Mysqli API to connect to the Mysql database

The variable $host should contain only the HOST of your mysql server, which has nothing to do with Apache and nothing to do with HTTP:

<?php

$host = 'localhost';
$usuario = 'root';
$senha = 'minhasenha';
$banco = 'meubanco';

$link = mysqli_connect($host, $usuario, $senha, $banco);

if (mysqli_connect_error()) {
    printf('Erro de conexão: %s', mysqli_connect_error());
    exit;
}

if (!mysqli_set_charset($link, 'utf8')) {
    printf('Error ao usar utf8: %s', mysqli_error($link));
    exit;
}

if ($result = mysqli_query($link, 'SELECT * FROM nome')) {

    /* Pegando os dados */
    while ($row = mysqli_fetch_assoc($result)) {
        echo $row['nome'];
    }

    /* libera os resultados */
    mysqli_free_result($result);
} else {
    /*Trata o erro da query, se ocorrer*/
    printf('Erro na query: %s', mysqli_error($link));
    exit;
}

/* fecha a conexão */
mysqli_close($link);

Handling error in query:

Probably your query is wrong, so you commented:

With mysqli another error occurs, in the case of Mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given - Otávio Guilherme

As an example I made, have an if and an Else:

if ($result = mysqli_query($link, 'SELECT * FROM nome')) {
    ... SE OCORRER TUDO NORMAL ...
} else {
    ... SE TIVER UM ERRO NA QUERY ...
}

UTF-8

If not using UTF-8 remove this part:

if (!mysqli_set_charset($link, 'utf8')) {
    printf('Error ao usar utf8: %s', mysqli_error($link));
    exit;
}

Answer 2

Do the following if nothing I’ve been through works, it seems your php version has already removed mysql_select_db so do it with mysqli is that simple

define('usuario_bd', 'root');
define('senha_bd', '');
define('nome_bd', 'loja');

$conexao = mysqli_connect('localhost', usuario_bd, senha_bd, nome_bd);
$retorno = mysqli_query($conexao,"SELECT * FROM nome");

while($row = mysqli_fetch_array($retorno)) {             
 echo $row["nome"];
    }  

Answer 3

Friend, alternatively you can use PDO, which is a more consistent way of using multiple databases.

The mysql_* functions have been deprecated from PHP 7.0 if you still use an older version of PHP and need to update PHP for some reason you will have problems with these functions.

You can use the code snippet below to connect to a mysql database.

try {
        $dsn = sprintf("mysql:host=%s;dbname=%s;charset=utf8", $host, $dbname);
        $connection = new \PDO($dsn, $user, $password);
        $connection->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);


} catch (\PDOException $exc) {
     echo $exc->getTraceAsString();
}

Below is an example search with PDO:

$statement = $connection->prepare("SELECT * FROM tabela WHERE id = :id");
        try {
            $statement->bindValue( ':id', $id, \PDO::PARAM_INT );
            $statement->execute();


        $resultado = $statement->fetch(\PDO::FETCH_OBJ);

        } catch (\PDOException $exc) {
            throw new \Exception('Erro ao executar ' . $exc->getMessage());
        }

Answer 4

Try editing your "mysql_connect" line for this.

mysql_connect('localhost', usuario_bd, senha_bd);