SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a201ff98b14728a5b6fa017238ed8b9c106639dd251b62cdc8841cbd35af8fe0' 
  AND token = 'QZZLr2Llt5KqrXRfhjWgyXHWK6IKQf0fo69X/QgLHbs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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