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Facts

Facts are key-value metadata attached to sources or objects.

Types of Facts

Built-in facts are collected automatically during scanning:

  • source.ext - File extension
  • source.size - File size in bytes
  • source.mtime - Modification timestamp
  • content.hash.sha256 - Content hash (when computed)

Imported facts come from external tools via the enrichment pipeline:

  • EXIF metadata: content.Make, content.Model, content.DateTimeOriginal
  • Geolocation: content.geo.city, content.geo.country
  • Media info: content.mime, content.duration
  • Any custom key-value pairs you choose to import

Namespaces

Facts are namespaced:

  • source.* - Facts about the file on disk (path, size, timestamps)
  • content.* - Facts about the content itself (stored on objects when hashed)

When querying, the content. prefix is optional: --where 'Make=Apple' is equivalent to --where 'content.Make=Apple'.

Value Types

Canon stores facts as:

  • Text: Strings like "Apple" or "image/jpeg"; enables string matching (=, ~ glob) and string modifiers (|lowercase, |stem)
  • Numbers: Integers or decimals like 1024 or 3.14; enables numeric comparisons (>1000) and the |bucket modifier
  • Timestamps: Unix timestamps; enables date modifiers (|year, |month) and date comparisons (>=2024-01-01)

Type hints can be provided during import to ensure correct parsing. See Enriching for details.