SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = 'cf02fc5bf6d7286b8528a7b355af97c3e79c14f5bc6f0e7d7b84fbe6fd61ecad' 
  AND token = 'MsrC8ZNXg29QD5CruxlRtZ0+SuPyFGvg7vIYJzgaTYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00771

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}