conexión Oracle y correcion de instalacion oracle 11G

Al ejecutar Run SQL command line (SQL*Plus) sale este mensaje cuando ejecuto una consulta

SP2-0640 Not connected

Solución

I was having the same problem but i sorted it out by doing the following:
1. Run SQL Command Line
2. Type Connect
3. Enter Username
4. Enter Pasword

Then you should get a message that the you are connected at this point you can access the database table. Thanks

CORREGIR LA INSTALACION DE ORACLE 11G PARA 64 BITS

https://jukarpenz.wordpress.com/2014/04/21/solution-to-problem-installing-install-oracle-database-11g-express-edition-oracle-xe-11g-r2-on-windows-server-2012-x64/
http://blog.mclaughlinsoftware.com/2011/09/13/oracle-11g-xe-installer/
http://betaroot.blogspot.pe/2014/05/instalacion-de-oracle-express-edition.html