SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3a2fc89046863e7390ca4f6d2dff9d90658653d539c81d5fa24d78e4fdba71f' 
  AND token = 'w4FB7Ay3DXpwdkG/qTSYlCuf38TrrW58WeAMb4oSG3w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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