# Database Design

## oauth\_applications

| Field             | Purpose                                                                                                |
| ----------------- | ------------------------------------------------------------------------------------------------------ |
| **id**            | Primary key, in case of using RDBMs                                                                    |
| **name**          | Application name                                                                                       |
| **uid**           | Unique ID, used as [*client identifier*](https://tools.ietf.org/html/rfc6749#section-2.2)              |
| **secret**        | Used together with `uid` for client authentication                                                     |
| **redirect\_uri** | Redirects the resource owner to this URI ([spec](https://tools.ietf.org/html/rfc6749#section-3.1.2))   |
| **scopes**        | Defines which [scopes](https://doorkeeper.gitbook.io/guides/configuration/scopes) the application uses |
| **confidential**  | Indicates whether client public or private                                                             |
| **created\_at**   | Creation date & time                                                                                   |
| **updated\_at**   | Date & time of latest update                                                                           |

If you set `enable_application_owner` configuration option then applications table also includes:

| Field           | Purpose                         |
| --------------- | ------------------------------- |
| **owner\_id**   | PK of the Resource owner record |
| **owner\_type** | Resource owner model name       |

## oauth\_access\_tokens

| Field                        | Purpose                                       |
| ---------------------------- | --------------------------------------------- |
| **id**                       | Primary key, in case of using RDBMs           |
| **resource\_owner\_id**      | PK of the resource owner record               |
| **application\_id**          | PK of the client token was issued for         |
| **token**                    | Token value                                   |
| **refresh\_token**           | Refresh token value (used to refresh a token) |
| **expires\_in**              | TTL of the token (in seconds)                 |
| **revoked\_at**              | Date & time when token was revoked            |
| **created\_at**              | Creation date & time                          |
| **scopes**                   | Access token scopes                           |
| **previous\_refresh\_token** | Previous refresh token value                  |

If you enabled `use_polymorphic_resource_owner` configuration option then your database must have additional columns:

| Field                     | Purpose                   |
| ------------------------- | ------------------------- |
| **resource\_owner\_type** | Resource owner model name |

## oauth\_access\_grants

| Field                   | Purpose                               |
| ----------------------- | ------------------------------------- |
| **id**                  | Primary key, in case of using RDBMs   |
| **resource\_owner\_id** | PK of the resource owner record       |
| **application\_id**     | PK of the client token was issued for |
| **token**               | Token value                           |
| **expires\_in**         | TTL of the token (in seconds)         |
| **redirect\_uri**       | Redirect URI                          |
| **revoked\_at**         | Date & time when token was revoked    |
| **created\_at**         | Creation date & time                  |
| **scopes**              | Access token scopes                   |

In case you enabled PKCE flow, your access grants table will include:

| Field                       | Purpose                    |
| --------------------------- | -------------------------- |
| **code\_challenge**         | Code challenge value       |
| **code\_challenge\_method** | Code challenge method name |


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