Count number of records in a MySql table with PHP?

Just do it that way here.

$sql = "SELECT * FROM usuarios";
$resultado = count($sql);
echo $resultado;

When you make a query in the database, you can pass Count:

$sql = "SELECT COUNT(*) FROM fruit WHERE calories > 100";

$query = mysql_query("SELECT count(*) as total from tabela");
$resultado = mysql_fetch_assoc($query);
echo $resultado['total'];

PHP has a function only to count the rows without using Count(*) which is mysqli_num_rows() . This allows you to reuse the query result.

$QUERY = "SELECT * AS Quantidade FROM BancoA.tabelaA";
$executa_query = mysqli_query($conexao, $QUERY);
$conta_linhas = mysqli_num_rows($executa_query);
echo $conta_linhas;