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documentation/database.md

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+# Database Documentation for Embedder
+
+Embedder utilizes **SQLite3** to manage its user system and store metadata for uploaded files.
+
+---
+
+## Databases:
+
+### `media.db`
+- **Description**: Manages the user system and image metadata.
+  
+### `session.db`
+- **Description**: Handles login session data to keep users logged in over time.
+
+---
+
+## Tables:
+
+### Media Table
+
+#### TypeScript Interface: `MediaRow`
+
+- **Description**: Represents a row in the media table.
+- **Fields**:
+  - `id`: Optional number or string
+  - `path`: String
+  - `expire`: Date object
+  - `username`: Optional string
+
+#### SQL Structure
+
+- `id`: INTEGER
+- `path`: TEXT
+- `expire`: INTEGER
+- `username`: TEXT
+
+---
+
+### User Table
+
+#### TypeScript Interface: `UserRow`
+
+- **Description**: Represents a row in the user table.
+- **Fields**:
+  - `id`: Optional number
+  - `username`: String
+  - `hashed_password`: Any
+  - `salt`: Any
+
+#### SQL Structure
+
+- `id`: INTEGER
+- `username`: TEXT
+- `hashed_password`: BLOB
+- `expire`: INTEGER
+- `salt`: BLOB
+
+---
+
+## Database Interactions (`lib/db.ts`)
+
+### `createDatabase(version: number)`
+
+- **Description**: Initializes the database schema.
+- **Parameters**:
+  - `version`: Number indicating the version of the database schema.
+  
+### `createUser(username: string, password: string)`
+
+- **Description**: Inserts a new user record into the user table.
+- **Parameters**:
+  - `username`: String representing the user's name.
+  - `password`: String representing the user's password.
+
+### `insertToDB(filename: string, expireDate: Date, username: string)`
+
+- **Description**: Adds a new media record into the media table.
+- **Parameters**:
+  - `filename`: String representing the filename of the uploaded media.
+  - `expireDate`: Date object indicating when the media should expire.
+  - `username`: String representing the user's name.
+
+### `getPath(id: number | string)`
+
+- **Description**: Retrieves the path for a specific file using its ID.
+- **Parameters**:
+  - `id`: Number or string representing the file's ID.
+
+### `deleteId(database: string, id: number | string)`
+
+- **Description**: Removes a record from the database.
+- **Parameters**:
+  - `database`: String representing the name of the database.
+  - `id`: Number or string representing the ID of the record to be removed.
+
+### `expire(database: string, column: string, expiration: number)`
+
+- **Description**: Sets an expiration date for a particular database row.
+- **Parameters**:
+  - `database`: String representing the name of the database.
+  - `column`: String representing the name of the column in which the date should be set.
+  - `expiration`: Number representing the Unix timestamp when the record should expire.
+