Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f39b257e8a5906d86f8ec5abbbdbfa67ee3612e2d0de114cd0d8477be2ffc245' 
  AND token = 'SjTFzE/uCv4KriCNSqkFuRlW/JB3uhA/euMuiVahhDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}