SQL>
SQL> define gname=idle
SQL>
SQL> column global_name new_value gname
SQL>
SQL> select lower(user) || '@' ||
2 substr( global_name, 1, decode( dot,
3 0, length(global_name),
4 dot-1) ) global_name
5 from (select global_name, instr(global_name,'.') dot
6 from global_name );
GLOBAL_NAME
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rntsoft@XE
SQL> set sqlprompt '&gname> '
SQL>