I would like to know how to get the last row of a MySQL table, and put this number inside a PHP variable.
I tried this way:
require_once "../../models/conex.php";
$sql = "SELECT * FROM tabela ORDER BY id DESC LIMIT 1";
$query = $mysqli->query($sql);
$ultimaLinha = $query;
$mysqli->close();
But var_dump returns boolean false ...
Just to note, the problem was that in addition to forgetting fetch (which was pointed out by @rray), also had an error in the query, as it was passing the wrong field name.
After I put the
$query = $mysqli->query($sql) or die($mysqli->error);
At the suggestion of @rray, the error appeared:
Unknown column 'id' in 'order clause'
Then just include while with fetch , and correct the field name.
It looks like this:
require_once "../../models/conex.php";
$sql = "SELECT * FROM tabela ORDER BY idcerto DESC LIMIT 1";
$query = $mysqli->query($sql) or die($mysqli->error);
while ($dados = $query->fetch_assoc()) {
print_r($dados['idcerto']);
}
UPDATE
Following the guidance given by @DanielOmine in comments, I changed while to if , for two reasons:
while ; if it checks if the result does not return empty; The standard code:
require_once "../../models/conex.php";
$sql = "SELECT * FROM tabela ORDER BY idcerto DESC LIMIT 1";
$query = $mysqli->query($sql) or die($mysqli->error);
if ($dados = $query->fetch_assoc()) {
$idcerto = (int)(($dados['idcalc']) + 1);
echo $idcerto;
}
else{
echo "erro na obtenção da id";
}
?>
Implement this way and do not forget to recover the error, there may be some exceptions and you are not recovering.
Try this:
$leitura = "SELECT * FROM php_teste"; <== seu select
$resultado =mysqli_query($leitura) or die (mysqli_error());
if(mysqli_num_rows($resultado) <=0){
echo 'não tem nada';
} else {
while($mostra = mysqli_fetch_assoc($query)){
print_r($mostra);
}
}
Place:
$linha = $query->fetch_array(MYSQLI_ASSOC);
$variavel=$linha["NOME DA COLUNA DESEJADA"];