Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '250a34ec6d9adf1458518282b055c6b47b6012131e2ecab8a174c3f2d98a1cc6' 
  AND token = 'If0WRMl8dFDkdQfqix/nnEeAGQdwGaMRlVQt7VqmyWE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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