Hydration

How database rows are converted to PHP objects.

Table of contents

• Overview
• Built-in Hydration
  • With custom mapping

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Overview

Hydration is the process of converting raw database rows (associative arrays) into typed PHP DTO objects. Rowcast uses a Reflection-based hydrator by default that handles this automatically.

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Built-in Hydration

Hydration is performed by Rowcast’s built-in Hydrator:

1. Creates a new instance of the DTO class without calling the constructor
2. Maps each column value to the corresponding property
3. Converts values to declared PHP types using TypeConverterInterface
4. Sets the property values via Reflection

use AsceticSoft\Rowcast\DataMapper;

$mapper = new DataMapper($connection);

// Hydrate a single row
$user = $mapper->hydrate(User::class, [
    'id' => 1,
    'name' => 'Alice',
    'email' => 'alice@example.com',
]);

// Hydrate multiple rows
$users = $mapper->hydrateAll(User::class, $rows);

With custom mapping

use AsceticSoft\Rowcast\Mapping;

$mapping = Mapping::explicit(User::class, 'users')
    ->column('usr_email', 'email');

$user = $mapper->hydrate($mapping, [
    'id' => 1,
    'usr_email' => 'alice@example.com',
]);

The same hydration pipeline is used by findOne(), findAll(), and iterateAll().