SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = 'bd56ce0b497c58577d88ae111eb4d4b7086d6603eed1b321877bf49c6900ab85' 
  AND token = 'h38fxG7wZ32QXcb61myQQpzcdTwpdgr9Ulwx/HoYcqg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00792

JSON explain

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