# Items guide

Items are Cherrycake's conceptualization of the fundamental objects stored in a database. For example, in an e-commerce site, a product would be an Item, but also would a user, a product category or an invoice.

## Creating an Item class

Items always come from a database table, so let's imagine we have a database of movies and we want to define an [Item](/reference/core-classes/item.md) to work with the movies that are stored in our database, in a table called `movies` with the following fields:

| Field name       | Specs                                           |                                                        |
| ---------------- | ----------------------------------------------- | ------------------------------------------------------ |
| **`id`**         | `unsigned` `int` `auto_increment` `primary key` | The unique id to identify movies.                      |
| **`title`**      | `varchar`                                       | The name of the movie.                                 |
| **`summary`**    | `text`                                          | A summary of the movie plot.                           |
| **`year`**       | `year`                                          | The year the movie was released.                       |
| **`dateAdded`**  | `datetime`                                      | The date and time the movie was added to the database. |
| **`directorId`** | `unsigned` `int`                                | The id of the director in the `directors` table.       |

> You can get an SQL script to create this table in the [Cherrycake documentation examples repository](https://github.com/tin-cat/cherrycake-documentation-examples), in the [`/install/database/movies.sql`](https://github.com/tin-cat/cherrycake-documentation-examples/blob/master/install/database/movies.sql) file.

Items are [App classes](/guide/classes-guide.md#app-class-files) that extend the Cherrycake's [Item](/reference/core-classes/item.md) core class, so we create the `Movie` class in the file `/classes/Movie.class.php`, and it looks like this:

```php
<?php

namespace CherrycakeApp;

class Movie extends \Cherrycake\Item {
    protected $tableName = "movies";
    protected $fields = [
        "id" => [
            "type" => \Cherrycake\DATABASE_FIELD_TYPE_INTEGER
        ],
        "title" => [
            "type" => \Cherrycake\DATABASE_FIELD_TYPE_STRING
        ],
        "summary" => [
            "type" => \Cherrycake\DATABASE_FIELD_TYPE_TEXT
        ],
        "year" => [
            "type" => \Cherrycake\DATABASE_FIELD_TYPE_YEAR
        ],
        "imdbRating" => [
            "type" => \Cherrycake\DATABASE_FIELD_TYPE_FLOAT
        ]
    ];
}
```

We set some properties of the class to configure it:

* **`tableName`** The name of the table where the items are stored.
* **`fields`** A hash array to specify the field names and field types of the table. See [Database constants](/reference/core-modules/database.md#constants) for all the available field types. See [Item::$fields](/reference/core-classes/item/item-properties.md#fields) for more keys you can use here to customize how your Item works.

You can also set this other properties if you'll be using values different from the defaults:

* **`databaseProviderName`** The database provider name where this items are stored. The default is `main`
* **`idFieldName`** The name of the field that contains values to uniquely identify each item in the table. Defaults to `id`

With this we've already created a functional Item that can now represent a movie in our app with the added benefits of using Cherrycake Items.

Now, what can you do with your new `Movie` class? Let's see how to create a `Movie` object we can manipulate. Let's say we want to load the movie with id `15`:

```php
$movie = new Movie([
    "loadMethod" => "fromId",
    "id" => 15
]);
```

Field values for an [Item](/reference/core-classes/item.md) are accessed just like regular properties, like this:

```php
echo "{$movie->title} ({$movie->year})";
```

```
Brainstorm (1983)
```

{% hint style="success" %}
See this example working in the [Cherrycake documentation examples](https://documentation-examples.cherrycake.io/example/itemsGuideBasicUsage) site.
{% endhint %}

We can also update items on the database by using [Item::update](/reference/core-classes/item/item-methods.md#update), for example:

```php
$movie->update([
    "imdbRating" => 8.7
]);
```

Changing an Item's property manually and then calling [Item::update](/reference/core-classes/item/item-methods.md#update) without any parameters also works. This will do the same as the example above:

```php
$movie->imdbRating = 8.7;
$movie->update();
```

To remove an item from the database, use the [Item::delete](/reference/core-classes/item/item-methods.md#delete) method:

```php
$movie->delete();
```


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