# Solution to Database Path Issue

## Problem

The application was encountering the following errors when starting up:

```
Error running migration add_episode_ordering.py: no such table: podcasts
Error running migration add_podcast_tags.py: no such table: podcasts
Error running migration add_season_explicit_naming_format.py: no such table: episodes
```

And when accessing podcast pages:

```
sqlite3.OperationalError: no such column: podcasts.tags
```

## Root Cause

The issue was caused by a mismatch between where the application was looking for the database file and where the database file was actually located:

1. The application was configured to look for the database file at `sqlite:///podcastrr.db`, which is a relative path to a file in the root directory.
2. However, the actual database file was located in the `instance` directory (`instance/podcastrr.db`).
3. This caused the migrations to fail because they couldn't find the tables they were trying to modify.

## Solution

The solution was to update the database path in the application configuration to point to the correct location:

1. Modified `application.py` to change the default database path from `sqlite:///podcastrr.db` to `sqlite:///instance/podcastrr.db`.
2. This ensures that the application and all migrations look for the database file in the `instance` directory, which is where Flask stores instance-specific files by default.

## Changes Made

In `application.py`, the following change was made:

```python
# Before
SQLALCHEMY_DATABASE_URI=os.environ.get('DATABASE_URI', 'sqlite:///podcastrr.db')

# After
SQLALCHEMY_DATABASE_URI=os.environ.get('DATABASE_URI', 'sqlite:///instance/podcastrr.db')
```

## How to Verify the Solution

1. Run the application:
   ```
   python main.py
   ```

2. Verify that the application starts without any database-related errors.

3. Access a podcast page to verify that the "no such column: podcasts.tags" error is resolved.

## Preventing Similar Issues in the Future

To prevent similar issues in the future:

1. Always use consistent database paths across the application.
2. Consider using Flask's built-in `app.instance_path` to get the correct instance directory path.
3. Update the `.env.example` file to reflect the correct database path:
   ```
   DATABASE_URI=sqlite:///instance/podcastrr.db
   ```
4. Document the expected location of the database file in the README.md file.