Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c8f9b54d2cc1cd1e503041fee9d3c326e483ab8941e8fdd7e081d9b9cf7046e' 
  AND token = 'P/MrxXFGFJ4RnPqkeulrssxbZQW7ImKfavE4hVI8vaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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