Pdo Fetchall Array to One Dimensional

PDO fetchAll array to one dimensional

Take a look at example 2 in the manual. In your first query you can use:

$staff = $select->fetchAll(PDO::FETCH_COLUMN, 0);

And your second array will have the same form as the first array.

PDO fetch one column from table into 1-dimensional array

<?php
$sql = "SELECT `ingredient_name` FROM `ingredients`";
$ingredients = $pdo->query($sql)->fetchAll(PDO::FETCH_COLUMN);

PDO 'fetchAll' return rows with an extra array

fetchAll will return a two-dimensional array.

• The first dimension is each row.
• The second dimension is each field (key/value pair) within that row.

$resultset[0]['fieldname'] will return the value of fieldname in the first row of the result set.

You're expecting fetchAll to return a single row whereas that's what fetch does.

So to keep it simple:

• If your result set will always only return one row, use fetch.
• If your result set could return multiple (or zero) rows, use fetchAll and then for each to iterate through each row.

PDO retrieves two-dimensional array instead of one-dimensional array

PDO retrieves exactly what you ask it for.

To get a one-dimensional array you have to use PDO::FETCH_COLUMN instead of PDO::FETCH_ASSOC

return $dbh->query("SELECT $column FROM $table" )->fetchAll(PDO::FETCH_COLUMN);

Note that your query is critically prone to SQL injection. PDO shouldn't be used that way. Do not try to automate SQL. It's already perfectly automated. Use a literal query like SELECT foo,bar FROM baz WHERE id=1 instead. There is not that much writing you're probably afraid of, and there will be not that much use of this function in a real world code as you probably hope for.

OR

use a ready-made query builder, such as Doctrine.

In PHP, is it possible to get a 1 dimmensional array using PDO?

Using the constant PDO::FETCH_COLUMN:

$columnNumber = 0;
$rows = $preparedStatement->fetchAll(PDO::FETCH_COLUMN, $columnNumber);

This way you'll get exactly what you proposed.

You can also do the following:

$columnNumber = 0;
$rows = $preparedStatement->fetchAll(PDO::FETCH_COLUMN|PDO::FETCH_UNIQUE, $columnNumber);

This way you'll get an array with unique values.

Source: http://www.php.net/manual/en/pdostatement.fetchall.php

PHP PDO FetchAll - format of array

Although you are asking for PDO::FETCH_ASSOC constant (by calling fetchAll(PDO::FETCH_ASSOC) you'll get only single value), yet there is an even more intelligent fetch mode - PDO::FETCH_COLUMN

$ul1 = 0;
$sql = "SELECT word FROM tbl WHERE catid > ? ORDER BY RAND() LIMIT 3";
$stmt = $pdo->prepare($sql);
$stmt->execute([$ul1]);
$data = $stmt->fetchAll(PDO::FETCH_COLUMN);

var_dump($data);

this way you'll get just a simple one-dimensional array which you can address the most natural way:

$test = $data[2];

or iterate over with

foreach ($data as $word)
{
    echo "$word</br>\n";
}

Create single array from MySQL with PHP/PDO

What you need is PDO::FETCH_COLUMN mode:

$sql = "SELECT name FROM " . $this->table_name . "  ORDER BY id";
$prep_state = $this->db_conn->prepare($sql);
$prep_state->execute();

// 0 indicates first column of result
$names = $prep_state->fetchAll(PDO::FETCH_COLUMN, 0); 
print_r($names);
// then do what you want.

---

Related Topics