SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e804e91ae4af3294d1efd58ecd667b72fe54502155005fd908d00f435503c4f' 
  AND token = 'HTODz6Wc/VoTX43aoYCxCCqf9sZhSSrvJJHxAoEISv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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