SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = '09de83f769d68363a480909e85c05fcc71437f68255365afc30235c3b34808bc' 
  AND token = '7A/uImiK+Z/uEedCNJHPsElZidQuYl+fOPNkgcFxeiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00839

JSON explain

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