SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa6731bbaa746ef01eb4957810fe2f0956ae1faab96b71559270318605a829d7' 
  AND token = 'vfNd0eCrp2cFsgLRx7izHlfg2rKOXcCQxDUY/DFsbBE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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