SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd93bd97de07555beca0b6534ee1dd8e151ba682d9ed7487a485d4bfdcb163151' 
  AND token = 'SmmDgZZnMq00KoSib/5i5uO6mMuGquT5gzSW7hMNxJA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}