SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da736fd018c4bd39ae730f3e131302de8f2293270f291359131992c71ea70fcc' 
  AND token = '0tal6R0D8yxWiJq0tdhhyRn+JpvIQIClWXo/M9jYxlo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}