SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1be206627a4b6f54e5accba45a519b9e0bd2854a944d0a778ba5e3827adf9c5f' 
  AND token = 'WFuMbXDzsqg5kb740HI6Qv3ukr0/xXKRIFCMxJIsnRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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