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(PHP 5 >= 5.1.0, PECL pdo >= 0.1.0)
PDOStatement::fetchAll — Returns an array containing all of the result set rows
$fetch_style
[, mixed $fetch_argument
[, array $ctor_args
= array()
]]] )
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
column-index
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 have 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
.
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.
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" }