SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75326a790ba1077a14363abbe7c4aaa89f10a3aa2755d0741c5398e449864c42' 
  AND token = '+pYgmn//24kfkYu5AIhM+06kCr5Rz41zqnkZQ8twWG8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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