Provider identifiers
A provider identifier names a record within a provider's namespace and entity model, independently of a local file path or displayed title.
A provider identifier refers to a record in a particular catalogue. The useful key includes its namespace and entity context, not just the printable value.
A value is only one part of the reference
Consider this invented key model:
(provider namespace, entity type, identifier string)
| Reference | Interpretation |
|---|---|
| Provider A, movie, "42" | A movie record in A |
| Provider B, movie, "42" | Another provider's movie record |
| Provider A, series, "42" | A potentially different entity class in A |
| Local library, item, "42" | A server's own item relationship |
The identical string does not establish that those references point to the same thing. A catalogue's actual API determines which entity classes share or separate identifier namespaces.
A local path is another kind of address. Renaming a file need not change its associated work, and one work can have several local file versions.
Keep opaque keys as keys
Identifiers can contain prefixes, leading zeroes or UUID punctuation. Converting them into integers or stripping characters for cosmetic reasons can change the reference.
The key generally should not be reverse-engineered into a title, release date or quality judgment. A large numeric value does not imply a higher-resolution movie.
IMDb and MusicBrainz show concrete schemes. Their values have different forms and entity models.
Identity and descriptive values can change independently
A provider can correct a title without creating a new work. A record merge can also introduce redirects or another canonical relationship under that provider's rules.
Those changes need a defined interpretation. A stored old identifier does not become the key to an unrelated record merely because its display text changed.
The selected record still needs the intended scope. A valid music release identifier placed into a field intended for a recording can make subsequent lookup use the wrong entity.
An Emby item has several identity relationships
A library item can have a server-local identity, provider references and one or more media resources. They serve different actions.
In Emby, Metadata Manager is the documented place for reviewing a match and its related fields. Compare the provider namespace and entity being corrected, rather than replacing every identifier with the same number.
A provider work ID also does not prove an exact edition match for subtitles. Subtitle release matching considers the extra timing and content evidence.