I am working on SQL developer and installed oracle Xpress also. So I want to use explain plan to know stats.
But it says
Unable to gather statistics please unsure user has correct access.
The statistic feature requires that the user is granted select on v_$sesstat, v_$statname and v_$session.
SQL> connect hr/password
SP2-0310: unable to open file "$ORACLE_HOME/rdbms/admin/utlxplan.sql"
what I have to do to get prvileges and to use explain plan
It sounds like you're trying to use autotrace.
Log in as system or sys and grant SELECT on those views listed in the error above TO HR.