./sync.py --help
Sync 1m ETH candles for the last 90 days:
./sync.py candles --exchange=bitfinex --symbol=tETHUSD
If you want to sync more data use --start=2020-01-01 for example. All syncs where candles are missing at the beginning of the range will catch up from start to [first candle in db], and then also sync [last candle in db] to now() (if --end isn't specified).