Data dictionary

Name: SamHooks opportunity-change event fields
Creator: SamHooks
License: https://www.usa.gov/government-works

Every field we emit, mapped to the bulk-extract column it came from. The extract's exact header set is confirmed against each daily file; aliases are handled in the ingest layer.

Event field	Extract column	Type	Notes
`notice_id`	`NoticeId`	string	Stable ID; our dedupe key.
`title`	`Title`	string	Keyword matching runs against this field and `description`.
`naics`	`NaicsCode`	string\|null	6-digit NAICS; filter by prefix or exact.
`set_aside`	`SetASideCode`	string\|null	e.g. `SBA`, `8A`; matched case-insensitively.
`agency`	`Department/Ind.Agency`	string\|null	Issuing department/agency.
`posted_date`	`PostedDate`	string\|null	As published.
`response_deadline`	`ResponseDeadLine`	string\|null	Deadline changes emit `opportunity.changed`.
`status`	`Active`	string\|null	Normalized; cancellations/awards emit their own event kinds.
`description`	`Description`	string\|null	Plain-text notice description from the extract's final column (flattened; nominal 5,000-char upstream cap, occasionally exceeded). `null` when the extract row has none.
`description_link`	`Link` (or derived)	string	Always present: the SAM.gov notice URL.
`changed_fields`	computed	string[]	Which fields differed since the previous daily snapshot.
`event`	computed	enum	`opportunity.new\|changed\|cancelled\|awarded` from snapshot-to-snapshot diffing.