0-5-2-understand-c001

name	0.5.2-understand-c001
description	[0.5.2] commit point: the precise instant when a transaction transitions from active to committed; the log sequence nu

understand-c001

CALL NUMBER: deep_rollback.c001 DEFINITION: commit point: the precise instant when a transaction transitions from active to committed; the log sequence number position where durable persistence is guaranteed

Invoke this skill to understand c001 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_rollback

• c006 (d1): commit LSN: the log sequence number position of the commit log record; the fence above which all prior transaction writes are durable
• c009 (d1): commit completion: the terminal state transition from active to committed; releases all locks held exclusively and schedules release of shared locks per protocol
• c002 (d2): commit log record: the write-ahead log entry that atomically records the commit point; contains transaction identifier and commit LSN
• c003 (d2): commit sequence number (CSN): a monotonically incrementing identifier assigned to each committed transaction; provides total ordering of committed state changes
• c008 (d2): commit acknowledgment: the confirmation signal returned to the client indicating successful durable persistence of the transaction
• c010 (d2): commit promise: the contractual guarantee to the user that transaction effects are durable and will survive any subsequent system restart

CONSUMERS (what needs this)

c002, c015

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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.)