This question is an exact duplicate of:
I am trying to get data form SqlServer2008 in SP2010 with the hep of BCS.
I have created External List Successfully,but when I go to my Site I get following error:
Unable to display this Web Part. To troubleshoot the problem, open this Web page in a Microsoft SharePoint Foundation-compatible HTML editor such as Microsoft SharePoint Designer. If the problem persists, contact your Web server administrator. I have tried second approach on this link
I am not getting what is going wrong.
I am just trying to get 100 records Thanks in advance.