Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4165996945c40f5a5cb5ed8d84c632d10d0ad7b7bcdd0c4b9138ad914ec7f51' 
  AND token = 'cn3f819EpJDUCV8f68TjvZ81OvHBMDgwI1lEAimEGfk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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