How do you delete tablespaces?

Use the DROP TABLESPACE statement to remove a tablespace from the database. When you drop a tablespace, Oracle Database does not place it in the recycle bin. Therefore, you cannot subsequently either purge or undrop the tablespace. You must have the DROP TABLESPACE system privilege.

Table of Contents

How do I get rid of undo tablespace?

In order to remove datafiles added unnecessarily to UNDOTBS1 and reduce its size:

Create a new undo tablespace as : SQL> create undo tablespace UNDOTBS2 datafile.
Change parameter UNDO_TABLESPACE. SQL> alter system set UNDO_TABLESPACE=UNDOTBS2;
Drop UNDOTBS1.

How do I delete datafiles?

You use the DROP DATAFILE and DROP TEMPFILE clauses of the ALTER TABLESPACE command to drop a single datafile or tempfile. The datafile must be empty. (A datafile is considered to be empty when no extents remain allocated from it.)

Can we drop undo tablespace?

The undo tablespace to be dropped must be in the `empty` state and all rollback segments must be empty of undo segments. Only explicitly created undo tablespaces that have the suffix ‘. ibu’ can be dropped. The 2 implicit undo tablespaces cannot be dropped.

How do I drop a tablespace without datafile?

alter database datafile ‘/directory/filename’ offline drop; alter database open; drop tablespace ts_name; In the above steps, you tell Oracle that the missing datafile is now missing (offline drop).

How do I drop all tablespaces in Oracle?

Introduction to Oracle DROP TABLESPACE statement

First, specify the name of the tablespace that you want to drop after the DROP TABLESPACE keywords. Second, use the INCLUDE CONTENTS to delete all contents of the tablespace. If the tablespace has any objects, you must use this option to remove the tablespace.

How do I see current undo tablespace?

Activities

Use the following queries to view undo tablespaces and rollback segments: SELECT * FROM DBA_TABLESPACES WHERE CONTENTS = ‘UNDO’; SELECT * FROM V$PARAMETER WHERE NAME = ‘undo_tablespace’;
Use the following queries to view undo statistics: SELECT * FROM V$ROLLSTAT; SELECT * FROM V$UNDOSTAT;

Why does undo tablespace grow?

Question: What do I do to keep my UNDO tablespace from growing? Answer: The UNDO tablespace size is governed by the the undo_retention parameter. f its non-default and is set to a high value in order to enable a large flash recover area. Undo tablespace will tend to keep the old data till that time period.

Can I delete .dbf files?

No, seriously, never delete any . dbf and . lgf files manually. You won’t be able to access your database anymore.

How do I remove datafile from undo tablespace?

Drop Unused UNDO Tablespace
First, get a list of all the datafile for your UNDO tablespace. select file_name from dba_data_files where tablespace_name = ‘UNDOTBS’; Next, drop those data files one by one using alter tablespace drop datafile command as shown below. Now, drop the UNDO tablespace.

How do I find the size of my undo tablespace?

Check the Undo tablespace Usage in Oracle

Check the undo tablespace total, free and used space(Size in MB) in Oracle. SELECT a.tablespace_name,
Check the Active, expired and unexpired transaction space usage in Undo Tablespace.
Check undo usage by User or schema.

How do I delete a datafile from tablespace?

How to Drop a datafile from Tablespace in Oracle

Create a new oracle tablespace to hold moved objects.
Move all tables to the new tablespace.
Move all indexes to the new tablespace.
Move all other segments to the new tablespace.
Drop the old tablespace using the INCLUDING CONTENTS and datafiles option.

Can we drop tablespace in Oracle?

You can use the DROP TABLESPACE to remove a tablespace regardless of whether it is online and offline. However, it’s good practice to take the tablespace offline before removing it to ensure that no sessions are currently accessing any objects in the tablespace.

How do I add an undo tablespace?

Undo tablespaces can be created during database creation or using the CREATE UNDO TABLESPACE statement. — As part of database creation CREATE DATABASE rbdb1 CONTROLFILE REUSE UNDO TABLESPACE undotbs_01 DATAFILE ‘C:\Oracle\Ordata\TSH1ndo0101.

What does undo tablespace contains?

During database recovery, undo records are used to undo any uncommitted changes applied from the redo log to the datafiles. Undo records provide read consistency by maintaining the before image of the data for users who are accessing the data at the same time that another user is changing it.

How do I reduce the size of a DBF file?

The basic syntax for this command is: Alter database name datafile ‘file_name’ resize size; Where name is the name of the database, file_name is the name of the file and size is the new size to make this file. We can see this size change in the dba_data_files table as well as from the server.

How do I free up disk space in Oracle?

Free Up Disk Space

Log in as the oracle user.
Find and remove the dump files. Copy. find . – name OCSDMDW_Dump*.dmp | xargs rm –rf.

How do I know if undo tablespace is full?

What happens if undo tablespace is full?

THe UNDOTBS doesn’t behave like other tablespaces… the data is left in there and marked as unused when it’s no longer needed rather than being explicitly deleted.

What is stored in undo tablespaces?

Undo tablespace is a kind of permanent tablespace used by oracle database engine to manage undo data if you are running your database in automatic undo management mode. This undo data or undo records are generally used to: Roll back transactions when a ROLLBACK statement is issued. Recover the database.

How do I view undo tablespace?

How do I view undo tablespace files?

View Undo storage.

Use the following queries to view undo tablespaces and rollback segments: SELECT * FROM DBA_TABLESPACES WHERE CONTENTS = ‘UNDO’; SELECT * FROM V$PARAMETER WHERE NAME = ‘undo_tablespace’;
Use the following queries to view undo statistics: SELECT * FROM V$ROLLSTAT; SELECT * FROM V$UNDOSTAT;

How do I shrink datafile?

How do I reduce the size of my datafile?

Online shrink of objects towards the end of the datafile may allow you to reduce the datafile size. Move the SYSAUX objects with extents towards the end of the datafile to a temporary tablespace, reduce the datafile size and move them back.

How do I reclaim a tablespace space in Oracle?

After the data is pruned the datafiles contain unused space that needs to be reclaimed.
…
If the datafile name must remain the same do the following:

Create a new tablespace.
Move the segments to the new tablespace.
Resize the original datafile.
Move the segments back to the original tablespace.
Drop the new tablespace.

How do you delete tablespaces?