CREATE TABLE reviews_new (
	id TEXT PRIMARY KEY,
	task_id TEXT NOT NULL REFERENCES tasks(id),
	snapshot_n INTEGER NOT NULL,
	agent_session_id TEXT REFERENCES agent_sessions(id),
	vendor TEXT NOT NULL,
	model TEXT NOT NULL,
	state TEXT NOT NULL,
	result TEXT NOT NULL DEFAULT '',
	error TEXT NOT NULL DEFAULT '',
	created_at TEXT NOT NULL,
	finished_at TEXT NOT NULL DEFAULT '',
	UNIQUE (task_id, snapshot_n)
);
INSERT INTO reviews_new SELECT * FROM reviews;
DROP TABLE reviews;
ALTER TABLE reviews_new RENAME TO reviews;
CREATE UNIQUE INDEX reviews_session ON reviews(agent_session_id);