Plex Media Server 是一个媒体服务器，可以用来管理和串流电影、电视剧、音乐、照片等等媒体格式。
因为 Plex Media Server 运行在本地，所以几乎所有的信息都在本地的一个 SQLite 中，包括了 Library 的信息，多媒体的 meta 信息等等。
Plex Database 的位置
在 Linux 上（包括 NAS）：
$PLEX_HOME/Library/Application\ Support/Plex\ Media\ Server/Plug-in\ Support/Databases/com.plexapp.plugins.library.db
在 Debian/Ubuntu 下 Plex 数据在
/var/lib/plexmediaserver/Library/Application Support/Plex Media Server/
在 macOS 上：
~/Library/Application\ Support/Plex\ Media\ Server/Plug-in\ Support/Databases/com.plexapp.plugins.library.db
Windows 上：
"%LOCALAPPDATA%\Plex Media Server\Plug-in Support\Databases\com.plexapp.plugins.library.db"
Plex SQLite3
分析的时间是在 2022 年 10 月 8 号，未来 Plex 可能对表名和表结构有所改变，请注意。
目前一共有 81 张表，7 张虚拟表。有一些表可以通过名字猜测出来，比如 accounts 表就是 Plex 登录账号的表。
accounts # 登录的账户
activities # Plex 活动记录，比如更新 metadata, scanning
blobs
cloudsync_files # 看起来像是很多年前 Plex 就关闭了的 Cloud Sync 功能遗留下来的表
devices # 记录 Plex 登录的设备，包括 Chorme，Phone 等等
directories # Plex 能够扫描的文件夹列表
external_metadata_items
external_metadata_sources
fts4_metadata_titles_docsize
fts4_metadata_titles_icu_docsize
fts4_metadata_titles_icu_segdir
fts4_metadata_titles_icu_segments
fts4_metadata_titles_icu_stat
fts4_metadata_titles_segdir
fts4_metadata_titles_segments
fts4_metadata_titles_stat
fts4_tag_titles_docsize
fts4_tag_titles_icu_docsize
fts4_tag_titles_icu_segdir
fts4_tag_titles_icu_segments
fts4_tag_titles_icu_stat
fts4_tag_titles_segdir
fts4_tag_titles_segments
fts4_tag_titles_stat
hub_templates
library_section_permissions
library_sections # 仓库的设置
library_timeline_entries
locatables
location_places
locations_node
locations_parent
locations_rowid
media_grabs
media_item_settings
media_items
media_metadata_mappings
media_part_settings
media_parts # 包含了重要的媒体文件的路径
media_provider_resources
media_stream_settings
media_streams
media_subscriptions
metadata_item_accounts
metadata_item_clusterings
metadata_item_clusters
metadata_item_setting_markers
metadata_item_settings
metadata_item_views
metadata_items
metadata_relations
metadata_subscription_desired_items
play_queue_generators
play_queue_items
play_queues
plugin_permissions
plugin_prefixes
plugins
preferences
remote_id_translation
schema_migrations
section_locations
spellfix_metadata_titles_vocab
spellfix_tag_titles_vocab
sqlite_master
sqlite_sequence
sqlite_stat1
statistics_bandwidth
statistics_media
statistics_resources
stream_types
sync_schema_versions
synced_ancestor_items
synced_library_sections
synced_metadata_items
synced_play_queue_generators
synchronization_files
taggings
tags
versioned_metadata_items
view_settings
几张重要的表
专辑的打分，单曲的打分。
metadata_items
表 metadata_items 记录了所有媒体文件的 metadata 信息
表结构：
create table metadata_items
(
id INTEGER not null
primary key autoincrement,
library_section_id integer,
parent_id integer,
metadata_type integer,
guid varchar(255),
media_item_count integer,
title varchar(255),
title_sort varchar(255) collate NOCASE,
original_title varchar(255),
studio varchar(255),
rating float,
rating_count integer,
tagline varchar(255),
summary text,
trivia text,
quotes text,
content_rating varchar(255),
content_rating_age integer,
"index" integer,
absolute_index integer,
duration integer,
user_thumb_url varchar(255),
user_art_url varchar(255),
user_banner_url varchar(255),
user_music_url varchar(255),
user_fields varchar(255),
tags_genre varchar(255),
tags_collection varchar(255),
tags_director varchar(255),
tags_writer varchar(255),
tags_star varchar(255),
originally_available_at dt_integer(8),
available_at dt_integer(8),
expires_at dt_integer(8),
refreshed_at dt_integer(8),
year integer,
added_at dt_integer(8),
created_at dt_integer(8),
updated_at dt_integer(8),
deleted_at dt_integer(8),
tags_country varchar(255),
extra_data varchar(255),
hash varchar(255),
audience_rating float,
changed_at integer(8) default 0,
resources_changed_at integer(8) default 0,
remote integer,
edition_title varchar(255)
);
metadata_item_settings
metadata_item_settings 表中记录了媒体文件的打分 (rating)，播放次数(view_count)，播放位置(view_offset)，最后一次播放时间(last_viewed_at)。1
对于音乐库，专辑的 rating 在 metadata_items 表中，对于单曲的打分才在这张 metadata_item_settings 中。
SELECT mi.title, mi.rating album, mis.rating track
FROM metadata_item_settings mis
JOIN metadata_items mi on mis.guid = mi.guid
WHERE mi.parent_id = (SELECT id FROM metadata_items WHERE title LIKE '%<partial album title here>%');
用例
查看 playlists
metadata_type = 15 的时候表示该记录是 Playlist。
select title from metadata_items where metadata_type = 15;
查看某一个播放列表中的文件路径：
select file from media_parts as p left join media_items mi on mi.id = p.media_item_id
left join play_queue_generators as pqg on pqg.metadata_item_id = mi.metadata_item_id
left join metadata_items on metadata_items.id = pqg.playlist_id
where metadata_items.title = 'Playlist title';
查看所有条目
SELECT library_sections.name AS Libary, metadata_series.title as Series, metadata_season.'index' AS Season, metadata_media.title AS Title FROM media_items
INNER JOIN metadata_items as metadata_media
ON media_items.metadata_item_id = metadata_media.id
LEFT JOIN metadata_items as metadata_season
ON metadata_media.parent_id = metadata_season.id
LEFT JOIN metadata_items as metadata_series
ON metadata_season.parent_id = metadata_series.id
INNER JOIN section_locations
ON media_items.section_location_id = section_locations.id
INNER JOIN library_sections
ON library_sections.id = section_locations.library_section_id;