How to Store PHP Arrays in a Database: 5 Practical Methods

1. Store with serialize()

PHP’s built‑in serialize() converts an array into a storable string while preserving keys and nested structures. Example:

$data = ['name' => '张三', 'age' => 28, 'hobbies' => ['阅读', '游泳']];
$serialized = serialize($data);

Insert $serialized into a TEXT column via PDO or MySQLi. Retrieve the string and restore the original array with unserialize():

$original_array = unserialize($fetched_string);

2. Store as JSON with json_encode()

JSON provides language‑agnostic readability. Encode the array:

$json_string = json_encode($data, JSON_UNESCAPED_UNICODE);

Save the resulting string in a TEXT or LONGTEXT column. When reading, decode back to an associative array:

$array = json_decode($fetched_json, true);

3. Normalize into a related table

When the array represents multiple entities (e.g., order items), store each element as a separate row in a child table linked by a foreign key.

INSERT INTO orders (user_id, created_at) VALUES (123, NOW()); -- get order_id
INSERT INTO order_items (order_id, product_name, quantity) VALUES (1001, '笔记本', 2);

Wrap the inserts in a transaction to ensure consistency, and retrieve combined data with JOIN queries.

4. Store as a comma‑separated string with implode()

Suitable for simple one‑dimensional indexed arrays of strings:

$tags = ['php', 'mysql', 'html'];
$tag_string = implode(',', $tags);

Save $tag_string in a VARCHAR or TEXT field. Retrieve and split back with explode():

$tags_array = explode(',', $fetched_string); // trim elements as needed

5. Store Base64‑encoded serialized data

When the field must avoid special characters or you need lightweight obfuscation, encode the serialized or JSON string with Base64.

$raw = serialize($data);
$encoded = base64_encode($raw);
// store $encoded
$restored = unserialize(base64_decode($fetched_encoded));

Decode with base64_decode() and then unserialize() (or json_decode() if JSON was used).