PDOStatement->fetch
PDOStatement->fetchColumn
PDOStatement
PHP Manual

# PDOStatement->fetchAll

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

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

### Descripción

array PDOStatement::fetchAll ([ int `$fetch_style`= PDO::FETCH_BOTH [, int `$column_index` [, array `$ctor_args`= array() ]]] )

### Lista de parámetros

`fetch_style`

  Controls the contents of the returned array as documented in PDOStatement::fetch(). 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.

`column_index`

  Returns the indicated 0-indexed column when the value of `fetch_style` is PDO::FETCH_COLUMN. Defaults to 0.

`ctor_args`

  Arguments of custom class constructor.

### Valores retornados

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.

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 SORT BY clauses in SQL to restrict results before retrieving and processing them with PHP.

### Ejemplos

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);
?>`

El resultado del ejemplo seria:

    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);
?>`

El resultado del ejemplo seria:

    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));
?>`

El resultado del ejemplo seria:

    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"
      }
    }

### Ver también

- 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

PDOStatement->fetch
PDOStatement->fetchColumn
PDOStatement
PHP Manual