SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a98f492318a27aa0df7da0d8a76872de00345b239c010c3741f6ea46aa155de2' 
  AND token = 'uEQEZUlv+3LTXLGf8aVo4WpQ/HKwA8JtmIU1qS8Gxj0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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