How To Find Table Fragmentation
Jul 22, 2011A query to find the table fragmentation.
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Table Space Fragmentation
May 4, 2011I got the error ORA-01653: unable to extend table <OWNER.TABLE_NAME> by <BYTE> in tablespace <TABLESPACE> in my production database. But I could see 4GB of free space available in the tablespace. But this was resolved after increasing the Tablespace size by 1 more GB. So I wanted to know how I can I reclaim the 4GB space ?
While searching in internet I got few tips like there will be a fragmentation in the tablespace, the free space available in the tablespace may not be a continuous block. To avoid this we need to reorganize the tables using ALTER TABLE <TABLE_NAME> MOVE <TABLESPACE>; command.
But in my tablespace there are huge number of tables exists I cannot do reorganization of all the tables. So I need to know how to identify particularly what are the tables has more fragmentation? so that I can go for reorganizing those tables only.
My Database version in 9.2.0.7
Tablespaces are Locally Managed
SQL & PL/SQL :: Removing Table Fragmentation?
Aug 5, 2012To remove fragmentation which is the best method.
First one :
-----------------
1)Created a backup table from the Fragmented table (This table is a partitioned one).
2)Analyzed this table.
3)DROP the Fragmented table
4)Inserted the backuped up data from backup table to the Re-created table.
5)Analyze this table.
Second method
-------------------
1) Create a backup table newly, with PCTFREE =0
2) Inserted the data from Fragmented table ( This is a partitioned table) to backup table
3) Analyzed this table.
4) Truncate Fragmented table
4) Did Exchange partition of Fragmented table with Backup table.
The second method is not found to be removing the Fragmentation. Before the fragmentation was 28% after Second method the fragmentation is still the same. While the first method the fragmentation reduced to 16%.
Query used to find Fragmentation.
select table_name,
round((blocks*8),2) "table size kb",
round((num_rows*avg_row_len/1024),2) "actual data in table kb",
round((blocks*8),2)- round((num_rows*avg_row_len/1024),2) "wasted space kb",
[code]...
Performance Tuning :: Remove Table Fragmentation
Dec 29, 2011I have tried below steps for removing the table fregmentation but for some table i am not getting good result here.
1. It will collect the data which are having more than 100MB fragmentation.
select owner,table_name,blocks,num_rows,avg_row_len,round(((blocks*8/1024)),2)||'MB' "TOTAL_SIZE", round((num_rows*avg_row_len
/1024/1024),2)||'Mb' "ACTUAL_SIZE", round(((blocks*8/1024)-(num_rows*avg_row_len/1024/1024)),2) ||'MB' "FRAGMENTED_SPACE" from
dba_tables where owner in('a','b','c','d') and round(((blocks*8/1024)-(num_rows*avg_row_len/1024/1024)),2)
> 100 order by 8 desc;
2. then move the object(table) to the same tablespace.
alter table abc move;
alter table bcd move;
alter table efg move;
3. also rebuild the dependent objects.
alter index abc_PK rebuild online;
4. Then analyze the table which are having more than 100MB of fragmentation.
exec dbms_stats.gather_table_stats('a','abc');
exec dbms_stats.gather_table_stats('b','bcd');
exec dbms_stats.gather_table_stats('c','cdf');
after that when check the table fragmentation, i am getting the same result, which i have collected from the 1st query.
How To Remove Fragmentation
Sep 24, 2012I have table of 60 gb(indexes 60gb ) and it is subject to fragmentation around 10gb .
I m going to remove fragmentation . As i know i have three options
1.expdp/impdp .
2.CTAS (create table ........as.......) with parallel option .
3.Moving table into another tablespace with parallel option .
I have 4 physical and 4 logical cores(total 8 cores) on server .
SQL & PL/SQL :: Row-movement And Fragmentation?
May 29, 2012find out whether the rowmovement option in a partitioned table will cause fragmentation or not?
View 3 Replies View RelatedDoes Update On A Partitioned Column Cause Fragmentation
Apr 11, 2008Does "Update on a Partitioned Column" cause fragmentation ?
See example below :
Suppose I have a table as below that has approx 3 million rows and growing :
1) Table ABC :
file_id number
status_flag varchar2(1)
file_Content clob
date_created date
2) This table is list partitioned on Column "status_flag".
Column "status_flag" can take 3 values "A" or "B" or "C"
3) A file_id can transition from 1 "Status_flag" to another. [ A--> B , C--> B, B-->C, A --> C, etc ]
This means its possible to UPDATE the "status_flag " - the partitioned column.
Question :
-------------
1) Would the movement of rows from 1 partition to another cause fragmentation ?
2) Or Instead, should this be achieved by maintaining 3 tables - 1 each for every "status_Flag" as Table_A, Table_B, Table_C
This would mean that, if file_id 1, changes "status_flag" from 'A' to 'B' :
-- The corresponding row from Table_A will be created in Table_B
--- The same will be deleted from Table_A
This would still cause fragmentation ... with the overhead of Inserting a CLOB column from 1 table to another.
3) How to determine how much percent of the table is fragmented ?
PL/SQL :: Delete Millions Of Rows And Fragmentation
Mar 18, 2013i have deleted 20 lak rows from a table which has 30 lak rows,
and i wanted to release the fragmented space, what is the procedure other than exp/imp or alter table move
and also the recommended way to do this prod env... (coalesce /alter move etc.. )
db version is 11.2
Fragmentation / Defragmentation Of Space In Database
Jul 31, 2012Oracle DB version : 10.2.0.5.0
OS version HP-UX B.11.31 U ia64
DB size : 2TB
We have the above configuration for one of our oracle database. One of our DBA acts like he is only the person on this earth who is managing the process of fragmentation removal from the tablespaces in order to improve the performance and wastage of the space. He performs that task at weekends and takes one-off day extra. I am not sure how the fragmentation removal improves the performance and deallocates the space.
Is it compulsory to perform the rebuild process weekly in order to remove fragmented space from tablespaces? Do we have any other method to automatically re-organize objects occupying waste space?
Why the reuild of indexes using separate tablespace improves performance? is there any specifi reason for it?
SQL & PL/SQL :: Horizontal Fragmentation In Oracle 10g Express Edition?
Feb 28, 2012I want to do horizontal fragmentation of a table say employee. But fragmentation is often related to distributed databases. So i want to ask how can i do this on my single home computer? list out the steps that should be performed. I saw the concept of link but really failed to understand that.
View 14 Replies View RelatedText :: Query To Determine Index Fragmentation?
Mar 27, 2013Is this the right query to determine index fragmentation ?
SELECT AVG (tfrag)
FROM (SELECT /*+ ORDERED USE_NL(i) INDEX(i DR$TEXT_IDX$X) */
i.token_text,
(1
[code]...
The reason I am asking that before index rebuild it returned 86% but after rebuild (ALTER INDEX .. REBUILD) it returned
96% which does not make sense.
I did try ctx_report.index_stats but it takes more time to run.
Performance Tuning :: Fragmentation Can Reduce Performance In Query Times
Jun 16, 2010I have a question about database fragmentation.I know that fragmentation can reduce performance in query times. The blocks are distributed in many extents and scans process takes a long time. Oracle engine have to locate the address of the next extent..
I want to know if there is any system view in which you can check if your table or index has high fragmentation. If it's needed I will have to re-create, move or rebulid the table or index, but before I want to know if the degree of fragmentation is high.
Any useful script or query to do this, any interesting oracle system view?
How To Find Table For Script
Aug 19, 2010i have table like TWRCHAIN_WS_SUM. it is regularly updated by another object like procedure, function. how can i find which object is updating the particular table across the database.
View 4 Replies View RelatedUnable To Find A Table?
Mar 22, 2011why am i getting this?
SQL> SELECT TABLE_NAME,owner from dba_TABLES where TABLE_NAME in ('BSNL_ACCOUNT_DATA','BSNL_SERVICE_DATA','BSNL_PKG_DETAILS');
TABLE_NAME OWNER
------------------------------ ------------------------------
BSNL_ACCOUNT_DATA BPREAD
BSNL_SERVICE_DATA BPREAD
but the table exists
SQL> select count(*) from BPREAD.BSNL_PKG_DETAILS;
COUNT(*)
----------
3704
SQL> select TABLE_NAME,owner from dba_TABLES where TABLE_NAME='BSNL_PKG_DETAILS';
no rows selected
why is it showing no rows even if the table exists
Find Out Row Count From Each Table?
May 6, 2009I have written a script to get count of each tables of a schema.
DECLARE CURSOR c1 IS
select distinct table_name from all_tab_columns where OWNER='PLAY';
countrows NUMBER;
[Code].....
Find Out Row Count From Each Table
Mar 31, 2009SQL> select count(*) from tab;
COUNT(*)
----------
63
I need to find out how many rows in each table.I've tried with cursor.
SQL & PL/SQL :: How To Find Table That Contains Certain Column
Nov 9, 2011To find out column in which table it is located.
View 1 Replies View RelatedSQL & PL/SQL :: How To Find Table And Column Name
May 14, 2013With Data in a table, is it possible to find out the table name and column name? Means i know the account number (data) of the table and with this data i want to find out column name and table name.
View 3 Replies View RelatedSQL & PL/SQL :: Find Constraint Name Of A Table
Dec 24, 2010I want to know constraint name of a particular table if it exists.Here are the queries that i tried to find the constraint name of a particular table but the results were 'no rows selected'.
Queries:
select constraint_name from user_cons_columns where table_name='x';
select constraint_name from user_constraints where table_name='x';
SQL & PL/SQL :: How To Find Which Table Is Last Updated
Apr 11, 2012I want to know that How to find which table got last updated and how to find last DDL and DML operation obtained in which table? here I know the table name
SQL> SELECT LAST_DDL_TIME FROM DBA_OBJECTS WHERE OBJECT_NAME='PREM';
LAST_DDL_
---------
20-MAR-12
SQL> TRUNCATE TABLE PREM;
Table truncated.
SQL> SELECT LAST_DDL_TIME FROM DBA_OBJECTS WHERE OBJECT_NAME='PREM';
LAST_DDL_
---------
10-APR-12
Note: With out enable the auditing I want to know that .
SQL & PL/SQL :: Find Out Duplicate Name From Table?
Oct 28, 2010i have a employee table .i want to find out duplicate name from this table.so i write following query
select empname from employee
having count(empname) >1
group by empname
i find the result but problem is how i can find out the same name if it have any space like ramkumar ram kumar both are same but above query did not.give this data. how i can solve it
SQL & PL/SQL :: How To Find Out Wrong Value From Table
Jan 13, 2011I've written the code (see below) and after run I get an error:
ORA-06502: PL/SQL: numeric or value error: Bulk Bind: Truncated Bind
I don't know how to find out the wrong value from table. How to find it out?
DECLARE
TYPE rowids IS TABLE OF ROWID;
r1 rowids;
type t_varchar is table of varchar2(50);
n1 t_varchar ;
cursor c1 is select e.rowid rid,msisdn_displayed
from the_table
where contract_id is not null;
BEGIN
OPEN c1;
[code].........
PL/SQL :: How To Find Max Date From A Table
Mar 2, 2013I have two table in the database. I want to find the maximum routine date for a case_id when the lock_date is between 20 jan to 29 jan 2012 .
But I am not getting actual output (Output routine_date should be "28-jan-2012" but I m getting "31-jan-2012")
Master
case_id lock_date
101 23-jan-2012
101 24-jan-2012
102 27-jan-2012
102 29-jan-2012
101 30-jan-2012
101 29-jan-2012
Routine (for routine work)
case_id routine_date
101 23-jan-2012
103 28-jan-2012
102 21-jan-2012
102 29-jan-2012
101 21-jan-2012
101 28-jan-2012
101 31-jan-2012
select m.case_id, r.routine_date from master m, routine r,
(select case_id, max(routine_date) from routine group by case_id) rr
where m.case_id=r.case_id
and m.case_id=rr.case_id
and r.routine_date=rr.routine_date
Find Special DML On A Table
Apr 12, 2013i'm just trying to find out DML Statements, that where executed on a special table at a defined time. By googeling i just found a statement to find out the last DML, that was executed on a table or something else. But i want to look into the past. How can i do this?
View 16 Replies View RelatedPL/SQL :: How To Find Sequence For A Table
May 14, 2013I've got plenty of sequences. How can I identify that what are the sequences acting on a table?
View 8 Replies View RelatedHow To Find Last Inserted Record In A Table
Oct 5, 2010I have a table where there is no sequence maintained and there is no time stamp column to track the inserted record.How do I find the latest inserted record in the table.
View 5 Replies View RelatedFind DDL Statement Executed On A Table?
May 19, 2011I want to know the DDL statements executed on a table. Example:
i have a table test1 with structure as below: test1 (aa number, bb varchar2(10))
After some period of time, one DDL statement to alter the column is issued.
alter table test1 modify (bb varchar2(30));
so new table structure is: test1(aa number, bb varchar2(30))
Basically i would like to find these 2 DDL statements executed on this table - test1, so that i compare which column get modified and what modification done.
Is this information stored in any data dictionary table?
note - audit, flashback option not enabled in this database.
What SQL Command To Find Index Of A Table
May 14, 20071) how to find a primary key of a table in oracle, for example if I want to drop a index in table , how do I find what is the primary key in a table so that I can issue that command.
P/s: I don't have OEM installed so I must use SQL command
Example of dropping the index
ALTER TABLE table_name
drop CONSTRAINT constraint_name;
For example:
ALTER TABLE supplier
drop CONSTRAINT supplier_pk;
SQL & PL/SQL :: Find Out Column Value In All Table In Whole Database
May 19, 2010I need the column name and table name which is having the particular value in the whole database.
E.g. :We have 'Scott' value in emp table emp_name column. and we have lot of tables. here we need emp_name and emp as emp table is having scott value in emP_name column.
SQL & PL/SQL :: Find Out Base Table Of Synonym?
Jun 10, 2011How to find out the base table of a synonym?
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