SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = '4f4a13f3081238189ba659e357cc3549b6698dee95472c29f46d51ef209828ca' 
  AND token = 'eRanjpqmZHUpT3UlTe5LVS5fUCXvfaCfQMa/EwlAKCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00776

JSON explain

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