How to add whole array to one field in database - sql

Question

I have tried everything, array_push, multidimensional array and so on and nothing worked for me.
Following situation:
try {
if (isset($_SESSION['list']) > 0) {
foreach($_SESSION['list'] as $id=> $quantity) {
$sQuery = "SELECT * FROM table WHERE id = '".$id."' ";
$oStmt = $db->prepare($sQuery);
$oStmt->execute();
while($aRow = $oStmt->fetch(PDO::FETCH_ASSOC)) {
$id = $aRow['id'];
$name = $aRow['name'];
$volume = $aRow['volume'];
}
$testar = array(array('name' => $name, 'volume' => $volume, 'quantity' => $quantity));
$sQuery = "INSERT INTO table (array_data, date) VALUES ('$testar', NOW())";
$oStmt = $db->prepare($sQuery);
$oStmt->execute();
print_r($testar);
}
}
else {
echo 'Nothing to add';
}
}
catch(PDOException $e) {
$sMsg = '<p>
Regelnummer: '.$e->getLine().'<br />
Bestand: '.$e->getFile().'<br />
Foutmelding: '.$e->getMessage().'
</p>';
trigger_error($sMsg);
}
when I print_r($testar); I get this:
Array ( [0] => Array ( [name] => test 1 [volume] => 1.50 [quantity] => 4 ) ) Array ( [0] => Array ( [name] => test 2 [volume] => 2.50 [quantity] => 5 ) ) Array ( [0] => Array ( [name] => test 3 [volume] => 2.50 [quantity] => 2 ) )
but when I add it to database I only see: ARRAY.
How is that possible?
What I want is to add the whole Array to one field in database. Is that possible and how can I arrange that?

Answer 1

Usually, a column in an SQL database should have only one value, not an array. If you have multiple values, you should values individually, either as separate columns if they are a set of totally different types of data, or else as a single column on multiple rows of a dependent table if the array is multiple values of the same type of data.
This rule comes from First Normal Form.
But if you really need to store a PHP array in one row, you can convert the PHP array into a string with PHP's serialize() function. This is better than implode() because serialize() preserves hash keys, arrays of arrays, etc.
$testar = array(array('name' => $name, 'volume' => $volume, 'quantity' => $quantity));
$testar_serialized = serialize($testar);
$sQuery = "INSERT INTO table (array_data, date) VALUES (?, NOW())";
$oStmt = $db->prepare($sQuery);
$oStmt->execute( array($testar_serialized) );

Answer 2

I would start looking at the implode function.
Than you can add all the elements in the array to the field in the database, represented as a string.

Answer 3

A few things:
You don't insert an array into an SQL table; you insert the values of it.
Your SQL table should have a "column" for each field (e.g. name, volume, quantity), and will get a "row" for each entry in the outer array.
You should not have a variable reference in your SQL. This is called an “SQL injection vector,” and (due to accident or malice) will eventually wreak havoc upon you.
What you should do where your INSERT is, is:
prepare your SQL statement once:
INSERT INTO table (name, volume, quantity) VALUES (?,?,?);
The ? mark where the SQL drivers will place your values, which you specify later.
This tells the database to get ready to accept (1 or more) inserts in this form, and
shows the database driver (PDO, mysqli, …) where to put the values when you later
call execute
For each row in the array:
call execute with the list of values, e.g. ->execute ($testar->[$i]->['name'], …