SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d4128196626c7279837559a57635cb3325b598f9a4efc792aa376829526744d' 
  AND token = 'N+y1aULyzYtXvjtQ4lo6C0OklamVOKeW9U07XbJ8QQQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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