SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = 'b353340c19173985d09c82b5c1f0f2f43272965333688c0753bee86dba9ffb85' 
  AND token = 'aaewc1BhCmZjphGOQJcoTgcaZX4anDNAq88cc7kQDEg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00993

JSON explain

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