Manually set the Oracle environment

Learn how to manually set the Oracle environment for database administration. Before running Oracle database administration utilities, set the ORACLE_HOME and ORACLE_SID environment variables. Oracle Corporation recommends defining these variables manually when using Oracle utilities, rather than in the system environment scope. Defining Oracle environment variables at the system environment scope can cause conflicts when running multiple versions of Oracle on the same machine. Note Do not set ORACLE_HOME on SUSE Linux platforms. Environment variable Description ORACLE_HOME This environment variable must be set before any commands are started. ORACLE_HOME must be set to the path of the top-level (root) directory containing the Oracle application files. Note Be consistent with the setting of ORACLE_HOME for a database. Certain database functions fail if this variable is set incorrectly, even if it is set to a valid path to the Oracle home directory (for example, a symbolic link). ORACLE_HOME must always be set to the same value as it was when the database was created. ORACLE_SID This environment variable is used to distinguish each unique database instance and therefore must be set to the database instance that you want to maintain or administer. To manually set the Oracle environment, enter one of the following sets of commands. Replace ORACLE_HOME with the path to Oracle. All examples assume that the database SID is tc. Windows systems: Copy set ORACLE_HOME=ORACLE_HOME set ORACLE_SID=tc Linux systems: Copy export ORACLE_HOME=ORACLE_HOME export ORACLE_SID=tc