SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6dca3587360bf5a89ed50a23b282f0421c2c9b6ba28841f15c71685005e863d' 
  AND token = 'Jym95S32OhZjBLKKY/5jSA9HGV+kZhbBcMQ2H4T40DI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}