
To determine the current version of Oracle SQL*Plus, execute the following command,
sqlplus -V
or
sqlplus -version
The output will be like,
SQL*Plus: Release 10.2.0.5.0 - Production

To determine the current version of Oracle SQL*Plus, execute the following command,
sqlplus -V
or
sqlplus -version
The output will be like,
SQL*Plus: Release 10.2.0.5.0 - Production