Now let's collect all the knowledge we have gained in one chapter.

Models

A Model is a class that represents a table from the database.

Model class structure

Model class should be inherited from the Model class.

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The structure of the Model class should be filled in by Field objects.

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Note

Some fields have non-optional parameters (arguments).

Manager

Manager allows tools to manipulate the data.

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Command for Migrations

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Note

Try the python3 if the python doesn't work.

Instances

To work with instances, you need to use different methods.

Create

1. Create a new Model class instance.

2. Fill in all necessary attributes.

3. Submit changes using the save() method that send a query to the database.

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Retrieve all

Return the iterable QuerySet containing database records.

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Retrieve one

Return the one database record as the Model class instance.

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Update

1. Retrieve data.

2. Reassign attributes of the Model class instance(s).

3. Submit changes using the save() method that send a query to the database.

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URL patterns

To receive the pk from the URL address, we need to use the specific syntax: <int:pk>, where:

• int is a type of value;

• pk is the name of the argument in the view function.