PHP 7.0.6 Released

PDOStatement::fetchAll

(PHP 5 >= 5.1.0, PHP 7, PECL pdo >= 0.1.0)

PDOStatement::fetchAll — Returns an array containing all of the result set rows

Description

public array PDOStatement::fetchAll ([ int $fetch_style [, mixed $fetch_argument [, array $ctor_args = array() ]]] )

Parameters

fetch_style

Controls the contents of the returned array as documented in PDOStatement::fetch(). Defaults to value of PDO::ATTR_DEFAULT_FETCH_MODE (which defaults to PDO::FETCH_BOTH)

To return an array consisting of all values of a single column from the result set, specify PDO::FETCH_COLUMN. You can specify which column you want with the fetch_argument parameter.

To fetch only the unique values of a single column from the result set, bitwise-OR PDO::FETCH_COLUMN with PDO::FETCH_UNIQUE.

To return an associative array grouped by the values of a specified column, bitwise-OR PDO::FETCH_COLUMN with PDO::FETCH_GROUP.

fetch_argument

This argument has a different meaning depending on the value of the fetch_style parameter:

PDO::FETCH_COLUMN: Returns the indicated 0-indexed column.
PDO::FETCH_CLASS: Returns instances of the specified class, mapping the columns of each row to named properties in the class.
PDO::FETCH_FUNC: Returns the results of calling the specified function, using each row's columns as parameters in the call.

ctor_args

Arguments of custom class constructor when the fetch_style parameter is PDO::FETCH_CLASS.

Return Values

PDOStatement::fetchAll() returns an array containing all of the remaining rows in the result set. The array represents each row as either an array of column values or an object with properties corresponding to each column name. An empty array is returned if there are zero results to fetch, or FALSE on failure.

Using this method to fetch large result sets will result in a heavy demand on system and possibly network resources. Rather than retrieving all of the data and manipulating it in PHP, consider using the database server to manipulate the result sets. For example, use the WHERE and ORDER BY clauses in SQL to restrict results before retrieving and processing them with PHP.

Examples

Example #1 Fetch all remaining rows in a result set


<?php
$sth = $dbh->prepare("SELECT name, colour FROM fruit");
$sth->execute();

/* Fetch all of the remaining rows in the result set */
print("Fetch all of the remaining rows in the result set:\n");
$result = $sth->fetchAll();
print_r($result);
?>

The above example will output something similar to:

Fetch all of the remaining rows in the result set:
Array
(
    [0] => Array
        (
            [name] => pear
            [0] => pear
            [colour] => green
            [1] => green
        )

    [1] => Array
        (
            [name] => watermelon
            [0] => watermelon
            [colour] => pink
            [1] => pink
        )

)

Example #2 Fetching all values of a single column from a result set

The following example demonstrates how to return all of the values of a single column from a result set, even though the SQL statement itself may return multiple columns per row.


<?php
$sth = $dbh->prepare("SELECT name, colour FROM fruit");
$sth->execute();

/* Fetch all of the values of the first column */
$result = $sth->fetchAll(PDO::FETCH_COLUMN, 0);
var_dump($result);
?>

The above example will output something similar to:

Array(3)
(
    [0] =>
    string(5) => apple
    [1] =>
    string(4) => pear
    [2] =>
    string(10) => watermelon
)

Example #3 Grouping all values by a single column

The following example demonstrates how to return an associative array grouped by the values of the specified column in the result set. The array contains three keys: values apple and pear are returned as arrays that contain two different colours, while watermelon is returned as an array that contains only one colour.


<?php
$insert = $dbh->prepare("INSERT INTO fruit(name, colour) VALUES (?, ?)");
$insert->execute(array('apple', 'green'));
$insert->execute(array('pear', 'yellow'));

$sth = $dbh->prepare("SELECT name, colour FROM fruit");
$sth->execute();

/* Group values by the first column */
var_dump($sth->fetchAll(PDO::FETCH_COLUMN|PDO::FETCH_GROUP));
?>

The above example will output something similar to:

array(3) {
  ["apple"]=>
  array(2) {
    [0]=>
    string(5) "green"
    [1]=>
    string(3) "red"
  }
  ["pear"]=>
  array(2) {
    [0]=>
    string(5) "green"
    [1]=>
    string(6) "yellow"
  }
  ["watermelon"]=>
  array(1) {
    [0]=>
    string(5) "green"
  }
}

Example #4 Instantiating a class for each result

The following example demonstrates the behaviour of the PDO::FETCH_CLASS fetch style.


<?php
class fruit {
    public $name;
    public $colour;
}

$sth = $dbh->prepare("SELECT name, colour FROM fruit");
$sth->execute();

$result = $sth->fetchAll(PDO::FETCH_CLASS, "fruit");
var_dump($result);
?>

The above example will output something similar to:

array(3) {
  [0]=>
  object(fruit)#1 (2) {
    ["name"]=>
    string(5) "apple"
    ["colour"]=>
    string(5) "green"
  }
  [1]=>
  object(fruit)#2 (2) {
    ["name"]=>
    string(4) "pear"
    ["colour"]=>
    string(6) "yellow"
  }
  [2]=>
  object(fruit)#3 (2) {
    ["name"]=>
    string(10) "watermelon"
    ["colour"]=>
    string(4) "pink"
  }
}

Example #5 Calling a function for each result

The following example demonstrates the behaviour of the PDO::FETCH_FUNC fetch style.


<?php
function fruit($name, $colour) {
    return "{$name}: {$colour}";
}

$sth = $dbh->prepare("SELECT name, colour FROM fruit");
$sth->execute();

$result = $sth->fetchAll(PDO::FETCH_FUNC, "fruit");
var_dump($result);
?>

The above example will output something similar to:

array(3) {
  [0]=>
  string(12) "apple: green"
  [1]=>
  string(12) "pear: yellow"
  [2]=>
  string(16) "watermelon: pink"
}

See Also

PDO::query() - Executes an SQL statement, returning a result set as a PDOStatement object
PDOStatement::fetch() - Fetches the next row from a result set
PDOStatement::fetchColumn() - Returns a single column from the next row of a result set
PDO::prepare() - Prepares a statement for execution and returns a statement object
PDOStatement::setFetchMode() - Set the default fetch mode for this statement

User Contributed Notes

Ant P.

7 years ago


You might find yourself wanting to use FETCH_GROUP and FETCH_ASSOC at the same time, to get your table's primary key as the array key:
<?php
// $stmt is some query like "SELECT rowid, username, comment"
$results = $stmt->fetchAll(PDO::FETCH_GROUP|PDO::FETCH_ASSOC);

// It does work, but not as you might expect:
$results = array(
    1234 => array(0 => array('username' => 'abc', 'comment' => '[...]')),
    1235 => array(0 => array('username' => 'def', 'comment' => '[...]')),
);

// ...but you can at least strip the useless numbered array out easily:
$results = array_map('reset', $results);
?>

Daniel Hofmann

6 years ago


PLEASE BE AWARE: If you do an OUTER LEFT JOIN and set PDO FetchALL to PDO::FETCH_ASSOC, any primary key you used in the OUTER LEFT JOIN will be set to a blank if there are no records returned in the JOIN.

For example:
<?php
//query the product table and join to the image table and return any images, if we have any, for each product
$sql = "SELECT * FROM product, image
LEFT OUTER JOIN image ON (product.product_id = image.product_id)";

$array = $stmt->fetchAll(PDO::FETCH_ASSOC);

print_r($array);
?>

The resulting array will look something like this:

Array
(
    [0] => Array
        (
            [product_id] => 
            [notes] => "this product..."
            [brand] => "Best Yet"
            ...

The fix is to simply specify your field names in the SELECT clause instead of using the * as a wild card, or, you can also specify the field in addition to the *. The following example returns the product_id field correctly:

<?php
$sql = "SELECT *, product.product_id FROM product, image
LEFT OUTER JOIN image ON (product.product_id = image.product_id)";

$array = $stmt->fetchAll(PDO::FETCH_ASSOC);

print_r($array);
?>

The resulting array will look something like this:

Array
(
    [0] => Array
        (
            [product_id] => 3
            [notes] => "this product..."
            [brand] => "Best Yet"
            ...

dyukemedia at gmail dot com

1 year ago


Getting foreach to play nicely with some data from PDO FetchAll()
I was not understanding to use the $value part of the foreach properly, I hope this helps someone else.
Example:
<?php 
$stmt = $this->db->prepare('SELECT title, FMarticle_id FROM articles WHERE domain_name =:domain_name');
            $stmt->bindValue(':domain_name', $domain);
            $stmt->execute();
            $article_list = $stmt->fetchAll(PDO::FETCH_ASSOC);
?>
which gives:

array (size=2)
  0 => 
    array (size=2)
      'title' => string 'About Cats Really Long title for the article' (length=44)
      'FMarticle_id' => string '7CAEBB15-6784-3A41-909A-1B6D12667499' (length=36)
  1 => 
    array (size=2)
      'title' => string 'another cat story' (length=17)
      'FMarticle_id' => string '0BB86A06-2A79-3145-8A02-ECF6EA5C405C' (length=36)

Then use:
<?php
foreach ($article_list as $row => $link) {
  echo  '<a href="'.  $link['FMarticle_id'].'">' . $link['title']. '</a></br>';
  }
?>

esw at pixeloution dot removeme dot com

5 years ago


Interestingly enough, when you use fetchAll, the constructor for your object is called AFTER the properties are assigned. For example:

<?php
class person {
    public $name;

    function __construct() {
       $this->name = $this->name . " is my name.";
    }
}

# set up select from a database here with PDO
$obj = $STH->fetchALL(PDO::FETCH_CLASS, 'person');
?>

Will result in ' is my name' being appended to all the name columns. However if you call it slightly differently:

<?php
$obj = $obj = $STH->fetchAll(PDO::FETCH_CLASS | PDO::FETCH_PROPS_LATE, 'person');
?>

Then the constructor will be called before properties are assigned. I can't find this documented anywhere, so I thought it would be nice to add a note here.

michael dot arnauts at gmail dot com

2 years ago


If you want to use PDO::FETCH_CLASS but don't like that all the values are of the type string, you can always use the __construct function of the class specified to convert them to a different type.

Another way is using mysqlnd, but it seems I had to recompile PHP for that.

<?php

class Cdr {
    public $a; // int
    public $b; // float
    public $c; // string
    
    public function __construct() {
        $this->a = intval($this->a);
        $this->b = floatval($this->b);
    }
     
}

// ...
$arrCdrs = $objSqlStatement->fetchAll(PDO::FETCH_CLASS, 'Cdr');

?>

fractalesque at gmail dot com

1 year ago


to fetch rows grouped by primary id or any other field you may use FETCH_GROUP with FETCH_UNIQUE:

<?php

//prepare and execute a statement returning multiple rows, on a single one
$stmt = $db->prepare('SELECT id,name,role FROM table');
$stmt->execute();
var_dump($stmt->fetchAll(PDO::FETCH_GROUP | PDO::FETCH_UNIQUE));

//returns an array with the first selected field as key containing associative arrays with the row. This mode takes care not to repeat the key in corresponding grouped array.

$result = array
 (1 => array
   ('name'=>'foo',
    'role'=>'sage',),
  2 => array
   ('name'=>'bar',
    'role'=>'rage',),);

// 'SELECT name,id,role FROM table' would result in that:

$result = array
 ('foo' => array
   ('id'=>1,
    'role'=>'sage',),
  'bar' => array
   ('id'=>2,
    'role'=>'rage',),);

?>

Anonymous

8 years ago


If no rows have been returned, fetchAll returns an empty array.

davey at php dot net

7 years ago


When passing PDO::FETCH_CLASS as the first argument, this method will accept the class name as the second option:

<?php
$query = $pdo->prepare($sql);

$result = $query->execute($values);

if ($result && $query->rowCount() > 0) {
    $records = $query->fetchAll(PDO::FETCH_CLASS, 'Some_Class');
    // $record is now an array of Some_Class objects
}
?>

- Davey

Hayley Watson

4 years ago


If you use the PDO::FETCH_CLASS | PDO::FETCH_PROPS_LATE flags to map columns to object properties, fetchAll() will use any __set() method your object has when carrying out the mapping.

harlequin2 at gmx dot de

7 years ago


There is also another fetch mode supported on Oracle and MSSQL: 
PDO::FETCH_ASSOC

> fetches only column names and omits the numeric index.

If you would like to return all columns from an sql statement with column keys as table headers, it's as simple as this:

<?php
$dbh = new PDO("DS", "USERNAME", "PASSWORD");
$stmt = $dbh->prepare("SELECT * FROM tablename");
$stmt->execute();
$arrValues = $stmt->fetchAll(PDO::FETCH_ASSOC);
// open the table
print "<table wdith=\"100%\">\n";
print "<tr>\n";
// add the table headers
foreach ($arrValues[0] as $key => $useless){
    print "<th>$key</th>";
}
print "</tr>";
// display data
foreach ($arrValues as $row){
    print "<tr>";
    foreach ($row as $key => $val){
        print "<td>$val</td>";
    }
    print "</tr>\n";
}
// close the table
print "</table>\n";
?>

info at yuriblanc dot it

7 months ago


Something missing in the doc.
If for instance you try to fetchAll(PDO::CLASS, "Class") it sometimes return an array of objects with NULL values, but the count of objects fetched correspond to table rows.

In this way works fine:
fetchAll(PDO::FETCH_CLASS | PDO::FETCH_PROPS_LATE, "Class");

For example

$stm = $pdo->prepare("SELECT * FROM Fruit");
$stm->execute();
$stm->fetchAll(PDO::FETCH_CLASS | PDO::FETCH_PROPS_LATE, "Fruit");

Anonymous

4 years ago


Note that fetchAll() can be extremely memory inefficient for large data sets. My memory limit was set to 160 MB this is what happened when I tried:



<?php

$arr = $stmt->fetchAll();

// Fatal error: Allowed memory size of 16777216 bytes exhausted

?>



If you are going to loop through the output array of fetchAll(), instead use fetch() to minimize memory usage as follows:



<?php

while ($arr = $stmt->fetch()) {

    echo round(memory_get_usage() / (1024*1024),3) .' MB<br />';

    // do_other_stuff();

}

// Last line for the same query shows only 28.973 MB usage

?>

akira at etnforum dot com

1 year ago


There may be some user who needs to upgrade their MySQL class to PDO class. The way of fetching results were changed from while loop into a foreach loop. For the people who wish to fetch the results in a while loop, here is a simple trick.

<?php

$db = new DB();
$query = $db->prepare("SELECT * FROM CPUCategory");
$query = $db->execute();
$result = $db->fetchAll();
var_dump($result);

?>

The Output will be:
array(2) {
    [0]=> array(2) {
        ["ccatid"]=> int(1)
        ["ccatname"]=> string(5) "Intel"
    }
    [1]=> array(2) {
        ["ccatid"]=> int(2) 
        ["ccatname"]=> string(3) "AMD"
    }
}

Never look like the output of old function.
[ORIGINAL STYLE] mysql_fetch_array($query)
[   MYSQL CLASS] $db->fetch_array($query)

And you may give up.
But there is a simple way to use while loop to fetch the results.

<?php

$db = new DB();
$query = $db->prepare("SELECT * FROM CPUCategory");
$query = $db->execute();
$result = $db->fetchAll();
$row = array_shift($result);
// If you need to fetch them now, put it in a while loop just like below:
// while($row = array_shift($result)) { ... }
    
var_dump($row);

?>

The Output will be in a single array with while loop returns TRUE:
array(2) {
    ["ccatid"]=> int(1)
    ["ccatname"]=> string(5) "Intel"
}

So after fetching this row, while loop runs again and fetch the next row until all row has fetched, then the while loop will return false. (Just like the old function did)

When you need to upgrade to PDO class, not much code needs to be modified and remember.

janniet at kiekies dot net

1 year ago


If you want to fetch rows as an object for which you have not defined a class, you can do:
<?php
$result = $q->fetchAll(PDO::FETCH_OBJ);
?>

mxrgus

6 years ago


In method body:

return $pstmt->fetchAll() or die("bad");

will not return correct value, but "1" instead.

mrshelly at hotmail dot com

7 years ago


PHP fetchAll Data From SQL Server 2005 
if field's data type is varchar(nvarchar), only fetch 255 chars. but the "text" data type is ok.

so, notice! to change the 'varchar' or 'nvarchar' (length > 255) to 'text' data type..

hope to help u.

<?php

$user = 'sa';
$pass = 'pass';

$conn = new PDO('mssql:host=127.0.0.1; dbname=tempdb;', $user, $pass);

$mainSQL = "SELECT field_varchar, field_text FROM table1";
$sth = $conn->prepare($mainSQL);
$sth->setFetchMode(PDO::FETCH_ASSOC);
$sth->execute();
$retRows = $sth->fetchAll();
// the field_varchar field only to fetch 255 chars(max)
// the field_text is ok.

var_dump($retRows);

unset($sth); unset($conn);

?>

Dennis

5 years ago


Error:
SQLSTATE[HY000]: General error: 2014 Cannot execute queries while other unbuffered queries are active. Consider using PDOStatement::fetchAll(). Alternatively, if your code is only ever going to run against mysql, you may enable query buffering by setting the PDO::MYSQL_ATTR_USE_BUFFERED_QUERY attribute.

If you're using something like:

while ($row = $query->fetchObject()) {
    [...]
}

try using this instead:

$rows = $query->fetchAll(PDO::FETCH_CLASS, 'ArrayObject');

foreach ($rows as $row) {
    [...]
}

stas at metalinfo dot ru

9 years ago


Note, that you can use PDO::FETCH_COLUMN|PDO::FETCH_GROUP pair only while selecting two columns, not like DB_common::getAssoc(), when grouping is set to true.

Dean S.

6 months ago


Using fetchAll() with the fetch types PDO::FETCH_GROUP and PDO::FETCH_ASSOC, PDO::FETCH_CLASS will always use the first column in the selected table as the key for the row in the output...

ramon at monztro dot com

3 years ago


If you are trying to call PDOStatement::fetchAll and is not getting the result set as expected (empty instead), check if you called PDOStatement::execute first.

Remember PDOStatement::fetchAll does not execute the query, it just mounts the array. 

:)

GyoreG

1 year ago


If you would like to get the result as "key-value-pairs", like:

Array(
    [key1] => "value1"
    [key2] => "value2"
)

then you can do it by calling fetchAll with PDO::FETCH_GROUP | PDO::FETCH_COLUMN parameters. 

<?php
  $result = $query->fetchAll(PDO::FETCH_GROUP|PDO::FETCH_COLUMN);
?>