RENAME Table or Column or Index in Oracle

RENAME Table
You can rename an existing table in any schema except the schema SYS. To rename a table you must be either DB owner or Table owner.

Use RENAME TABLE to rename a table.

Syntax: RENAME TABLE table-Name TO new-Table-Name
Ex:- RENAME TABLE EMPLOYEE TO EMPLOYEE_ACT

If you have a view or foreign key that references the table, attempts to rename it will generate an error. Also if there are any check constraints or triggers on the table, attempts to rename it will also generate an error.

RENAME Column: Use the RENAME COLUMN to rename a column in a table.

ex: RENAME COLUMN EMPLOYEE.Employee_ID TO EMP_ID;

You can use ALTER TABLE and RENAME COLUMN to modify Column data type

ALTER TABLE EMPLOYEE ADD COLUMN EMP_ID NEWTYPE
UPDATE EMPLOYEE SET EMP_ID = Employee_ID
ALTER TABLE EMPLOYEE DROP COLUMN Employee_ID
RENAME COLUMN t. Employee_ID TO EMP_ID

If a view, trigger, check constraint, foreign key constraint then attempt to rename it will generate an error. Also RENAME COLUMN is not allowed if you have any open cursors that reference the column that is being altered.

If there is an index defined on the column then you can still rename. The index will update automatically to refer by its new name

RENAME Index: Use the RENAME Index to rename an index, you cannot rename indexes in SYS schema

Ex:- RENAME INDEX EMPLOYEE_ID_INDEX TO EMP_ID_INDEX

In case if there are any open cursors that reference the index being renamed then RENAME INDEX is not allowed .

Thanks

Satishbabu G, Oracle ACE

http://oracleracepxert.com

How to enable Oracle SQL*Net Client, Server and Listener Tracing

To enable tracing make sure TNS_ADMIN environment variable should be set and add below tracing parameters in sqlnet.ora. Pls note that any trace settings apply to all server processes so you need to careful when making changes on Prod, I would always suggest to test before applying changes on PRD.
Enable SQL*Net server and Client side tracing.
TRACE_LEVEL_CLIENT = SUPPORT
TRACE_UNIQUE_CLIENT = on
TRACE_LEVEL_SERVER = SUPPORT
TRACE_DIRECTORY_CLIENT = \tmp
TRACE_FILE_CLIENT = Client_Trace.log
TRACE_DIRECTORY_SERVER = \tmp
TRACE_FILE_SERVER = Server_Trace.log
TRACE_TIMESTAMP_ CLIENT = ON
DIAG_ADR_ENABLED= OFF

Starting from 11g and higher to enable client, server trace you need to add DIAG_ADR_ENABLED= OFF

SQL*Net Listener tracing
TRACE_FILE_LISTENER = Listener_Trace.log
TRACE_DIRECTORY_LISTENER = \tmp
TRACE_LEVEL_LISTENER = SUPPORT
DIAG_ADR_ENABLED_LISTENER_<LISTENER> = OFF

To start Listener Trace you need to set DIAG_ADR_ENABLED_<listener name> = OFF (must set to OFF)

To enable Tnsping Trace
TNSPING.TRACE_LEVEL = SUPPORT
TNSPING.TRACE_DIRECTORY = <Trace file path>

Enabling Dynamic Listener Tracing
LSNRCTL> set current_listener listener_ORCL
Current Listener is listener_ORCL
LSNRCTL> set trc_level 16
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
LISTENER parameter "trc_level" set to support
The command completed successfully
LSNRCTL> set trc_directory /oracle/diag/tnslsnr/host1/listener_orcl/trace
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
LISTENER parameter "trc_directory" set to /oracle/diag/tnslsnr/host1/listener_orcl/trace

Turn off dynamic tracing using:
LSNRCTL>set current_listener listener
LSNRCTL>set trc_level OFF


Thanks

Satishbabu Gunukula, Oracle ACE

http://www.oracleracexpert.com