# Databases

WROLPi has two major Postgresql databases, the main (API) database, and the map database.

## Main Database

This contains the tables for the API.

### Service

`postgresql@15-main.service`

### Tables

| Name             | Purpose                                                 | Relations                    | `/opt/wrolpi` File             |
|------------------|---------------------------------------------------------|------------------------------|--------------------------------|
| alembic_version  | Tracks Alembic migration.                               |                              | `alembic`                      |
| archive          | Data about a FileGroup Archive.                         | file_group_id, domain_id     | `modules/archive/models.py`    |
| channel          | Data about a video Channel.                             |                              | `modules/videos/models.py`     |
| collection       | A logical grouping of FileGroups.                       | tag_id                       | `wrolpi/collections/models.py` |
| collection_item  | Links a FileGroup to a Collection.                      | collection_id, file_group_id | `wrolpi/collections/models.py` |
| directory        | Directories in the media directory.                     |                              | `wrolpi/files/models.py`       |
| domains          | Groups Archives by shared URL domain.                   |                              | `modules/archive/models.py`    |
| download         | Data about what should be downloaded and when.          |                              | `wrolpi/downloader.py`         |
| ebook            | Data about FileGroups that are books.                   | file_group_id                | `wrolpi/files/ebooks.py`       |
| file_group       | Each record is a group of files that share a stem.      |                              | `wrolpi/files/models.py`       |
| inventory        | A collection of items.                                  |                              | `modules/inventory/models.py`  |
| item             | An item in an inventory.                                | inventory_id                 | `modules/inventory/models.py`  |
| map_file         | Data about PBF files (if they have been imported, etc.) |                              | `modules/map/models.py`        |
| tag              | Data about a Tag (name, color, etc.)                    |                              | `wrolpi/tags.py`               |
| tag_file         | A FileGroup that has been tagged.                       | tag_id, file_group_id        | `wrolpi/tags.py`               |
| tag_zim          | An entry (article) that was tagged in a Zim file.       | tag_id, zim_id, zim_entry    | `modules/zim/models.py`        |
| video            | Data about a FileGroup Video                            | file_group_id, channel_id    | `modules/videos/models.py`     |
| wrolpi_flag      | Long-term flags that have occurred in the API.          |                              | `wrolpi/flags.py`              |
| zim              | A Zim file                                              |                              | `modules/zim/models.py`        |
| zim_subscription | A recurring download of a Zim file.                     |                              | `modules/zim/models.py`        |

## Map Database

This contains tables for the OpenStreetMap.

### Service

`postgresql@15-map.service`