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tests/data/journal/ — real sqlite3-engine rollback-journal scenarios

Tier: real-engine artifact / minted input. Every file here is produced by the real SQLite engine (not hand-encoded bytes), driving a minted scenario chosen to exercise one rollback--journal anomaly arm. The recipe is deterministic; the journal nonce is engine-random, so the committed artifact is the bytes the engine actually wrote — reproduce the scenario to get an equivalent (not byte-identical) journal.

These fixtures back forensic/tests/hot_journal_anomaly.rs, which validates the audit_journal anomaly arms (HOT, CHECKSUM-MISMATCH, DUPLICATE-PAGE, DBSIZE-DELTA, and the cookie-based SCHEMA-CHANGE) against real engine output rather than self-encoded bytes. Negative-derived variants (a flipped checksum byte, an appended duplicate record, an edited mx_page) are produced in-test on owned Vec<u8> copies — the committed corpus is never mutated.

Files

File md5 size role
hot.db 6dfd120f216ff997b819bdc755ea6431 20480 main db beside the hot journal
hot.db-journal d428e2fcf8e6f3d9c71a58b18c6f4dcc 22016 Tier-A hot journal (valid magic, n_rec=5, DML only)
ddl_persist.db 0271673fb35215d80f313e5f549dbbaf 16384 main db after a committed ALTER TABLE
ddl_persist.db-journal fe785dd18b5eb58b6dd4176ae5864130 8720 Tier-B PERSIST journal (zeroed header) with the prior page-1 image

Ground truth (verified against the bytes)

  • hot.db-journal — valid journal magic d9d505f920a163d7, n_rec=5, mx_page=5, page_size=4096, sector 512. All 5 page images (pgnos 3, 2, 4, 5, 1) are checksum-valid (5/5). Page 1 is journaled, but the prior page-1 image's schema cookie (bytes[40..44] BE = 1) equals the live db's cookie (hot.db offset 40 = 1): the held transaction was DML only, so SCHEMA-CHANGE must not fire. HOT fires.
  • ddl_persist.db-journal — Tier-B (header zeroed on PERSIST commit). The prior page-1 image's schema cookie is 1; the live ddl_persist.db cookie is 2 — the ALTER TABLE advanced it. SCHEMA-CHANGE must fire, with both cookie values shown.

Recipes

Engine: SQLite 3.45.3 (sqlite3 CLI) / 3.50.4 (Python sqlite3 module) on macOS. The hot-journal scenario needs an open transaction whose journal is flushed to disk mid-flight, so it is driven from Python (which can hold a transaction open and copy the files); the DDL scenario is a plain sqlite3 script.

hot.db + hot.db-journal (Tier-A hot journal, DML only)

import sqlite3, os, shutil
con = sqlite3.connect("hot.db")
con.execute("PRAGMA page_size=4096")
con.execute("PRAGMA journal_mode=DELETE")
con.execute("CREATE TABLE t(id INTEGER PRIMARY KEY, v TEXT)")
con.executemany("INSERT INTO t(id,v) VALUES(?,?)",
                [(i, f"row-{i:04d}-"+"x"*40) for i in range(1, 201)])
con.commit()
# cache_size=1 forces the page cache to spill, writing the journal to disk
# mid-transaction:
con.execute("PRAGMA cache_size=1")
con.execute("BEGIN IMMEDIATE")
con.execute("DELETE FROM t WHERE id <= 50")
con.executemany("INSERT INTO t(id,v) VALUES(?,?)",
                [(i, f"new-{i:04d}-"+"y"*60) for i in range(300, 360)])
# WHILE the transaction is open, copy the db and its journal:
shutil.copyfile("hot.db", "<dest>/hot.db")
shutil.copyfile("hot.db-journal", "<dest>/hot.db-journal")
con.rollback(); con.close()

ddl_persist.db + ddl_persist.db-journal (committed-DDL PERSIST journal)

-- sqlite3 ddl_persist.db < recipe.sql
PRAGMA page_size=4096;
PRAGMA journal_mode=PERSIST;
CREATE TABLE u(id INTEGER PRIMARY KEY, name TEXT);
INSERT INTO u(id,name) SELECT value, 'name-'||value FROM generate_series(1,300);
ALTER TABLE u ADD COLUMN extra TEXT DEFAULT 'd';

PERSIST leaves the -journal on disk after the clean commit (header zeroed, bodies intact), carrying the prior page-1 image whose cookie pre-dates the ALTER.

License / redistribution

Minted by this project with the open-source SQLite engine (public domain). The artifacts carry no third-party content and are released under this repository's license; safe to commit and redistribute.