Query
CREATE TABLE source_cursors (
source_id TEXT NOT NULL,
cursor_key TEXT NOT NULL,
-- e.g. "gmail_history_id",
"calendar_sync_token"
cursor_value TEXT,
updated_at TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ','now')),
PRIMARY KEY (source_id, cursor_key),
FOREIGN KEY (source_id) REFERENCES sources(id) ON DELETE CASCADE DEFERRABLE INITIALLY DEFERRED
)