To reproduce this testdata, run sqlite3 and execute:
PRAGMA journal_mode = WAL;
CREATE TABLE t (x);
INSERT INTO t (x) VALUES (1);
INSERT INTO t (x) VALUES (2);
sl3 split -o generations/0000000000000000/wal/00000000 db-wal
cp db generations/0000000000000000/snapshots/00000000.snapshot
lz4 -c --rm generations/0000000000000000/snapshots/00000000.snapshot
Then execute:
PRAGMA wal_checkpoint(TRUNCATE);
INSERT INTO t (x) VALUES (3);
sl3 split -o generations/0000000000000000/wal/00000001 db-wal
Then execute:
PRAGMA wal_checkpoint(TRUNCATE);
INSERT INTO t (x) VALUES (4);
INSERT INTO t (x) VALUES (5);
sl3 split -o generations/0000000000000000/wal/00000002 db-wal
Finally, obtain the final snapshot:
PRAGMA wal_checkpoint(TRUNCATE);
cp db 00000002.db
rm db*
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