0-4-2-understand-commit-visibility-boundary

name	0.4.2-understand-commit_visibility_boundary
description	[0.4.2] temporal threshold in read_committed: a datum is visible iff its committing_transaction committed before the r

understand-commit_visibility_boundary

CALL NUMBER: deep_isolation_level.commit_visibility_boundary DEFINITION: temporal threshold in read_committed: a datum is visible iff its committing_transaction committed before the reading statement started

Invoke this skill to understand commit_visibility_boundary down to its primitives. The RELATIVE ROOT below is the least-fixed-point closure of everything it bundles from — the full import cone, grouped by the lib each prim comes from. Projected from a prover-typed KB (MAP/SWI-Prolog consistency gate): every reference below resolves.

THE RELATIVE ROOT (the import cone, by lib)

from deep_isolation_level

• committed_data (d1): database state resulting from successfully completed transactions; constitutes the visible universe for read_committed queries
• statement_start_timestamp (d1): logical moment recorded when each statement begins, establishing the visibility cutoff point for read_committed row versions

CONSUMERS (what needs this)

no_dirty_reads, statement_level_read_consistency

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Projected from the database transaction isolation and concurrency control KB (280 concepts / 214 relations) — consistency-typed by MAP; the facet list after the colon IS the cross-lib dependency web.

(leaf — this is an actual skill.)