SQL> explain plan for select storage_id, storage_sid from storages order by storage_id; Explained SQL> select * from table(dbms_xplan.display); PLAN_TABLE_OUTPUT -------------------------------------------------------------------------------- --------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost | --------------------------------------------------------------------- | 0 | SELECT STATEMENT | | | | | | 1 | INDEX FULL SCAN | STORAGES_PK | | | | --------------------------------------------------------------------- Note: rule based optimization 9 rows selected SQL> explain plan for select storage_id, storage_sid from storages order by note; Explained SQL> select * from table(dbms_xplan.display); PLAN_TABLE_OUTPUT -------------------------------------------------------------------------------- -------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost | -------------------------------------------------------------------- | 0 | SELECT STATEMENT | | | | | | 1 | SORT ORDER BY | | | | | | 2 | TABLE ACCESS FULL | STORAGES | | | | -------------------------------------------------------------------- Note: rule based optimization 10 rows selected SQL>