SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d82eecd4154969e477ae46d07f3ed881c562fafdeddf9ccce65aee761896a98' 
  AND token = 'DXr++7ESYeLSq4SHQ/rDSDuZul82JDK5y8Q/c4Nue6g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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