Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed85dc7a1f374ba095392604ee316470e047da561c802c33c972ae632bbe63a1' 
  AND token = '9u4TQNTZaV5DkwqKHuPi11PbfBTbMUjVN2AlSAH2GvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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