mysqli_result::fetch_assoc

mysqli_fetch_assoc

(PHP 5, PHP 7, PHP 8)

mysqli_result::fetch_assoc -- mysqli_fetch_assoc — Obtem uma linha do conjunto de resultados como uma matriz associativa

Descrição

Estilo orientado a objeto (metodo):

mysqli_result::fetch_assoc(): array

Estilo de procedimento:

mysqli_fetch_assoc(mysqli_result $result): array

Retorna uma matriz associativa que corresponde a linha obtida, ou null se não houverem mais linhas.

A função mysqli_fetch_assoc() é usada para retornar uma matriz associativa representando a próxima linha no conjunto de resultados representado pelo parâmetro result, aonde cada chave representa o nome de uma coluna do conjunto de resultados.

Se duas ou mais colunas do resultado tiverem o mesmo nome do campo, a ultima coluna terá precedencia, Paa acessar as outra coluna(s) com o mesmo nome, você pode acessar o resultados com índices númericos usando a função mysqli_fetch_row() ou adicionar apelidos.

Nota: Os nomes de campos retornados por esta função diferenciam maiúsculas e minúsculas.

Nota: Esta função define campos NULL como o valor null do PHP.

Parâmetros

result: Somente no estilo procedural: Um objeto mysqli_result retornado por mysqli_query(), mysqli_store_result(), mysqli_use_result() ou mysqli_stmt_get_result().

Valor Retornado

Retorna uma matriz que corresponde a linha obtida null se não houverem mais linhas no conjunto de resultados.

Exemplos

Exemplo #1 Estilo orientado a objeto

<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}
 
$query = "SELECT Name, CountryCode FROM City ORDER by ID DESC LIMIT 50,5";

if ($result = $mysqli->query($query)) {

    /* fetch associative array */
    while ($row = $result->fetch_assoc()) {
        printf ("%s (%s)\n", $row["Name"], $row["CountryCode"]);
    }

    /* free result set */
    $result->close();
}

/* close connection */
$mysqli->close();
?>

Exemplo #2 Estilo de procedimento

<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

$query = "SELECT Name, CountryCode FROM City ORDER by ID DESC LIMIT 50,5";

if ($result = mysqli_query($link, $query)) {

    /* fetch associative array */
    while ($row = mysqli_fetch_assoc($result)) {
        printf ("%s (%s)\n", $row["Name"], $row["CountryCode"]);
    }

    /* free result set */
    mysqli_free_result($result);
}

/* close connection */
mysqli_close($link);
?>

O exemplo acima produzirá:

Pueblo (USA)
Arvada (USA)
Cape Coral (USA)
Green Bay (USA)
Santa Clara (USA)

Veja Também

mysqli_fetch_array() - Fetch the next row of a result set as an associative, a numeric array, or both
mysqli_fetch_row() - Obtém uma linha do resultado como uma matriz numerada
mysqli_fetch_object() - Fetch the next row of a result set as an object
mysqli_query() - Executa uma consulta no banco de dados
mysqli_data_seek() - Ajusta o ponteiro do resultado para uma linha arbritaria no conjunto de resutados

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User Contributed Notes 6 notes

down

Miller ¶

10 years ago

I often like to have my results sent elsewhere in the format of an array (although keep in mind that if you just plan on traversing through the array in another part of the script, this extra step is just a waste of time).

This is my one-liner for transforming a mysqli_result set into an array.
<?php
$sql = new MySQLi($host, $username, $password, $database);

$result = $sql->query("SELECT * FROM `$table`;");
for ($set = array (); $row = $result->fetch_assoc(); $set[] = $row);
print_r($set);
?>

Outputs:
Array
(
    [0] => Array
        (
            [id] => 1
            [field2] => a
            [field3] => b
        ),
    [1] => Array
        (
            [id] => 2
            [field2] => c
            [field3] => d
        )
)

I use other variations to adapt to the situation, i.e. if I am selecting only one field:
<?php
$sql = new MySQLi($host, $username, $password, $database);
$result = $sql->query("SELECT `field2` FROM `$table`;");
for ($set = array (); $row = $result->fetch_assoc(); $set[] = $row['field2']);
print_r($set);
?>
Outputs:
Array
(
    [0] => a
    [1] => c
)

Or, to make the array associative with the primary index (code assumes primary index is the first field in the table):
<?php
$sql = new MySQLi($host, $username, $password, $database);
$result = $sql->query("SELECT * FROM `$table`;");
for ($set = array (); $row = $result->fetch_assoc(); $set[array_shift($row)] = $row);
print_r($set);
?>
Outputs:
Array
(
    [1] => Array
        (
            [field2] => a
            [field3] => b
        ),
    [2] => Array
        (
            [field2] => c
            [field3] => d
        )
)

down

Enrique Garcia ¶

7 months ago

There is a difference between MariaDB and MySQL(>5.4) whether the input parameter (mysqli object) has data or is empty (it comes from a previus query).
-MariaDB:  you get an exception:
Fatal error: Uncaught TypeError: mysqli_fetch_assoc(): Argument #1 ($result) must be of type mysqli_result
-MySQL: you can continue, in spite of not having data in the mysqli object.

down

james dot phx at gmail dot com ¶

12 years ago

IMPORTANT NOTE:



If you were used to using code like this:



<?php

while(false !== ($row = mysql_fetch_assoc($result)))

{

    //...

}

?>



You must change it to this for mysqli:



<?php

while(null !== ($row = mysqli_fetch_assoc($result)))

{

    //...

}

?>



The former will cause your script to run until max_execution_time is reached.

down

-21

gilles dot falquet at unige dot ch ¶

5 years ago

Be careful when using fetch_assoc instead of fetch_row. If two columns of the result have the same column name, even if they are prefixed with different table names in the query, only one of them will be retained in the result. This is because the prefix is dropped (either by mysql or by this function)

For example if the query is 

     select p1.name, p2.name 
     from person p1, friend, person p2
     where p1.id = friend.person1 and p2.id = friend.person2

the arrays returned by fetch_assoc will be of the form

{'name' => 'bob'}
{'name' => 'anna'}

and not (as expected)

{'p1.name' => 'bob', 'p2.name' => 'alice'}
{'p1.name' => 'anna', 'p2.name' => 'irla'}

down

-32

Hesham Mohamed Sediek ¶

8 years ago

when you fetch the data from the query variable 
and try to fetch it again in another part of the script
from the same query variable , 
when you try to echo all data you have fetched,
it will not echo the data you have used in the first fetch 
(it will exceed the results you have used in the first fetch).......

Example :
<?php
$connect = new mysqli("localhost","root","root","elshamy")
 or die (mysqli_error());

$query=$connect->query("SELECT * FROM users ORDER BY id ASC");

$first_fetch=$query->fetch_array(MYSQLI_ASSOC);
echo $first_fetch['id']."===>".$first_fetch['user_name']."\n--------------------\n";

while($row=$query->fetch_array(MYSQLI_ASSOC)){

/*it will exceed the first 
id&user_name value that 
you have use in the first fetch*/

echo $row['id']."  ".$row['user_name']."<br/>"; 
}
?>

above example will echo :
1===>userA 
------------------------
2===>userB
3===>userC
4===>userD

down

-25

paul dot allsopp at inseego dot com ¶

6 years ago

The official example given here breaks a cardinal rule, and should be rectified.

while ($row = $result->fetch_assoc())...

...breaks the rule of "assignment in condition".

while (($x = $y->getZ()) !== false) or
while (($x = $y->getZ()) !== null)

...is the correct syntax.

Conditional statements should always check for a boolean

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