SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd370d8b8441f39f126f61db6f7525637c233ac3469aa1237b7b6e63fde4b6d9e' 
  AND token = 'gpvdU/3qR2RUZRVopePZ57n4rUYS3K8uTCLTwCzOm+0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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