SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f408ceb6bcb429521570bf886f3ec8d4c160b691ca21638ea4607d079912993' 
  AND token = 'vAgIKCmL2MuJi94uM/jf4KaSqEG7hqF6MI2Yk+YXN+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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