Converting from non partitioned to partitioned table

Hi gurus,
I need to convert non partition to partition table. Most flexible way is using DBMS_REDEFINITION package for this.
i dont have access to execute this package , when i asked for EXECUTION permission for my dev
CLIENT rejected with suggestion that
" DBMS_REDEFINITION is a very slow migration method which has never been used before here for such migrations
so I would not recommend using it as it could trigger bugs and unexpected side effects"
is it true?
what will be alternate method i can go far?
Please suggest
S

I don't think DBMS_REDEFINITION has bugs. However, you (and the client) need to be familiar with the steps involved.
Other than that, you'd have to build a partitioned table and insert data from the existing table. You can speed up the insert with direct path Parallel Insert.
You also need to build indexes on the new (partitioned) table. Define constraints if necessary. Execute grants to other schemas, if required.
Hemant K Chitale

Similar Messages

Move data from Non Partitioned Table to Partitioned Table

Hi Friends,
I am using Oracle 11.2.0.1 DB
Please let me know how can i copy /move the data from Non -Partitioned Oracle table to the currently created Partiotioned table.
Regards,
DB

839396 wrote:
Hi All,
Created Partitioned table but unable to copy the data from Non Partitioned table:
SQL> select * from sales;
SNO YEAR NAME
1 01-JAN-11 jan2011
1 01-FEB-11 feb2011
1 01-JAN-12 jan2012
1 01-FEB-12 feb2012
1 01-JAN-13 jan2013
1 01-FEB-13 feb2013into which partition should row immediately above ("01-FEB-13") be deposited?
[oracle@localhost ~]$ oerr ora 14400
14400, 00000, "inserted partition key does not map to any partition"
// *Cause: An attempt was made to insert a record into, a Range or Composite
//          Range object, with a concatenated partition key that is beyond
//          the concatenated partition bound list of the last partition -OR-
//          An attempt was made to insert a record into a List object with
//          a partition key that did not match the literal values specified
//          for any of the partitions.
// *Action: Do not insert the key. Or, add a partition capable of accepting
//          the key, Or add values matching the key to a partition specification>
6 rows selected.
>
SQL>
SQL> create table sales_part(sno number(3),year date,name varchar2(10))
2 partition by range(year)
3 (
4 partition p11 values less than (TO_DATE('01/JAN/2012','DD/MON/YYYY')),
5 partition p12 values less than (TO_DATE('01/JAN/2013','DD/MON/YYYY'))
6 );
Table created.
SQL> SELECT table_name,partition_name, num_rows FROM user_tab_partitions;
TABLE_NAME PARTITION_NAME NUM_ROWS
SALES_PART P11
SALES_PART P12
UNPAR_TABLE UNPAR_TABLE_12 776000
UNPAR_TABLE UNPAR_TABLE_15 5000
UNPAR_TABLE UNPAR_TABLE_MX 220000
SQL>
SQL> insert into sales_part select * from sales;
insert into sales_part select * from sales
ERROR at line 1:
ORA-14400: inserted partition key does not map to any partition
Regards,
DB

Dbms_redefinition used to convert a non partitioned table to partitioned

A table is created with below DDL
CREATE TABLE TEST1("EQUIPMENT_DIM_ID" NUMBER(9,0) NOT NULL ENABLE,
"CARD_DIM_ID" NUMBER(9,0),
"NH21_DIM_ID" NUMBER(5,0) NOT NULL ENABLE);
Interim table created with
CREATE TABLE INTERIM("EQUIPMENT_DIM_ID" NUMBER(9,0) NOT NULL ENABLE,
"CARD_DIM_ID" NUMBER(9,0),
"NH21_DIM_ID" NUMBER(5,0) NOT NULL ENABLE);
PARTITION BY RANGE ("EQUIPMENT_DIM_ID")
(PARTITION "P0" VALUES LESS THAN (1)
PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255
STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT) NOCOMPRESS ,
PARTITION "P1" VALUES LESS THAN (2)
PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255
STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT) NOCOMPRESS ,
Performed dbms_Redefinition (start,sync and finish) to get the table test1 data from nonpartitioned to partitioned one. At the end of table conversion, dbms_metadata.get_ddl shows like below
CREATE TABLE TEST("EQUIPMENT_DIM_ID" NUMBER(9,0) CONSTRAINT "SYS_C005605" NOT NULL ENABLE,
"CARD_DIM_ID" NUMBER(9,0),
"NH21_DIM_ID" NUMBER(5,0) CONSTRAINT "SYS_C005601" NOT NULL ENABLE);
PARTITION BY RANGE ("EQUIPMENT_DIM_ID")
(PARTITION "P0" VALUES LESS THAN (1)
PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255
STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT) NOCOMPRESS ,
PARTITION "P1" VALUES LESS THAN (2)
PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255
STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT) NOCOMPRESS
Can you help me how to hide or remove the "CONSTRAINT "SYS_C005605"" etc section showing in ddl for the table?The reason being if take this ddl definition and load in another database where it can give error in case same named constraint already exist.
Many thanks
Regards
Manoj Thakkan
Oracle DBA
Bangalore

Create your NOT NULL check constraints using ALTER TABLE and name them as you would a primary or foreign key ... with a name that makes sense.
I personally have a strong dislike for system generated naming and would be thrilled if this lazy practice of defining columns as NOT NULL during table creation went away.

Partition an Non Partition Table in 11.2.0.1

Hi Friends,
I am using Oracle 11.2.0.1 Oracle Database.
I have a table with 10 Million records and it's a Non Partitioned Table.
1) I would like to partition the table (with partition by range ) without creating new table . I should do it in the existing table itself (not sure DBMS_REDEFINITION is the only option ) (or) can i use alter table ...?
2) Add one partition which will have data for the unspecified range.
Please let me know the inputs on the above
Regards,
DB

Hi,
what is the advantage of using DBMS_REDEFINITION over normal method (create partition table,grant access,insert records)You can't just add a partition in a non-partitioned table. You need to recreate existing table to have it partitioned (you can't just start adding new partitions to existing non-partitioned table). Advantage of dbms_redefinition is that it is online operation to re-create an existing table and and your data always remains available during table recreation
I would like to know how to copy the object privileges,constraints,indexes from Non Partitioned table (sales) to Partitioned table (sales_part) which i am creating. will >DBMS_REDEFINITION.COPY_TABLE_DEPENDENTS help on this?First you need to tell us what method you are using to partition an existing table? If you are using dbms_redifiniiton, you really don't need to worry about triggers, indexex or constraints at all. Just follow any document which explains how to use dbms_redifinition. Dr. Tim has done a lot of work for dummys like us by writing documents for us. Follow this document.
http://www.oracle-base.com/articles/misc/partitioning-an-existing-table.php
If so can i use DBMS_REDEFINITION.COPY_TABLE_DEPENDENTS alone for copying the table dependents alone after i create partition table (or) it should be used along with >DBMS_REDEFINITION.START_REDEF_TABLE only?See above document which i mentioned.
Salman

11.2.0.3 Parallel delete on non-partitioned table

Friends and mentors...
I want to know more about parallel deleted and it's requirements...I have gone through Oracle manuals and articles but not able to understand exactly about parallel delete (dml) feature...
Task: Trying to delete large data (20 mil rows out of 60 mil) from non-partitioned table
Job frequency: Once every month
Oracle: 11.2.0.3
OS: Linux
Questions:
1. Any idea on best approach?
2. Do I need to have table partitioned to use /*+parallel */ hint?
3. If I use /*+parallel*/ hint in delete statement then do I need to use "alter session enable parallel dm1" ?
4. How to decided degree of parallelism (DOP)? is it good to use auto for DOP?
Currently I am planning to use parallel hint in delete statement, is this enough or need better plan?
thanks..

khallas301 wrote:
Friends and mentors...
I want to know more about parallel deleted and it's requirements...I have gone through Oracle manuals and articles but not able to understand exactly about parallel delete (dml) feature...
Task: Trying to delete large data (20 mil rows out of 60 mil) from non-partitioned table
Job frequency: Once every month
Oracle: 11.2.0.3
OS: Linux
Questions:
1. Any idea on best approach?
2. Do I need to have table partitioned to use /*+parallel */ hint?
3. If I use /*+parallel*/ hint in delete statement then do I need to use "alter session enable parallel dm1" ?
4. How to decided degree of parallelism (DOP)? is it good to use auto for DOP?
Currently I am planning to use parallel hint in delete statement, is this enough or need better plan?
thanks..
It appears that you believe that parallel is always faster than non-parallel; which is not true in every case.
The slowest part of any DELETE is the physical I/O.
How many parallel processes accessing the same table before the disk gets saturated?

Convert non-partition table to partition table

Hello Everybody
I am just want to ask about how to Convert non-partition table to partition table ?
Thanks
Ramez S. Sawires

Dear ARF
First of all thank you for replying me , second do u have any links talking about dbms_redefinition package
I am using Database Oracle 10g
Thanks
Ramez S. Sawires
Message was edited by:
Ramez S. Sawires

How to find out the Non Partitioned Tables used 2Gb on oracle

Hi team
how to find out the Non Partitioned Tables used > 2Gb on oracle where not is sys & system
regards

heres 1 I made earlier
set pagesize 999
set linesize 132
col owner format a25
col segment_name format a60
select owner,segment_name,segment_type,(bytes/1024/1024)"MB size"
from dba_segments
where owner not in ('SYS','SYSTEM','XDB','MDSYS','SYSMAN') -- edit for taste
and segment_type = 'TABLE'
having (bytes/1024/1024) > 2000
group by bytes, segment_Type, segment_name, owner
order by 4 asc

Oracle 11.2 - Perform parallel DML on a non partitioned table with LOB column

Hi,
Since I wanted to demonstrate new Oracle 12c enhancements on SecureFiles, I tried to use PDML statements on a non partitioned table with LOB column, in both Oracle 11g and Oracle 12c releases. The Oracle 11.2 SecureFiles and Large Objects Developer's Guide of January 2013 clearly says:
Parallel execution of the following DML operations on tables with LOB columns is supported. These operations run in parallel execution mode only when performed on a partitioned table. DML statements on non-partitioned tables with LOB columns continue to execute in serial execution mode.
INSERT AS SELECT
CREATE TABLE AS SELECT
DELETE
UPDATE
MERGE (conditional UPDATE and INSERT)
Multi-table INSERT
So I created and populated a simple table with a BLOB column:
SQL> CREATE TABLE T1 (A BLOB);
Table created.
Then, I tried to see the execution plan of a parallel DELETE:
SQL> EXPLAIN PLAN FOR
2 delete /*+parallel (t1,8) */ from t1;
Explained.
SQL> select * from table(dbms_xplan.display);
PLAN_TABLE_OUTPUT
Plan hash value: 3718066193
| Id | Operation             | Name     | Rows | Cost (%CPU)| Time     |    TQ |IN-OUT| PQ Distrib |
|   0 | DELETE STATEMENT      |          | 2048 |     2   (0)| 00:00:01 |        |      |            |
|   1 | DELETE               | T1       |       |            |          |        |      |            |
|   2 |   PX COORDINATOR      |          |       |            |          |        |      |            |
|   3 |    PX SEND QC (RANDOM)| :TQ10000 | 2048 |     2   (0)| 00:00:01 | Q1,00 | P->S | QC (RAND) |
|   4 |     PX BLOCK ITERATOR |          | 2048 |     2   (0)| 00:00:01 | Q1,00 | PCWC |            |
|   5 |      TABLE ACCESS FULL| T1       | 2048 |     2   (0)| 00:00:01 | Q1,00 | PCWP |            |
PLAN_TABLE_OUTPUT
Note
   - dynamic sampling used for this statement (level=2)
And I finished by executing the statement.
SQL> commit;
Commit complete.
SQL> alter session enable parallel dml;
Session altered.
SQL> delete /*+parallel (t1,8) */ from t1;
2048 rows deleted.
As we can see, the statement has been run as parallel:
SQL> select * from v$pq_sesstat;
STATISTIC                      LAST_QUERY SESSION_TOTAL
Queries Parallelized                    1             1
DML Parallelized                        0             0
DDL Parallelized                        0             0
DFO Trees                               1             1
Server Threads                          5             0
Allocation Height                       5             0
Allocation Width                        1             0
Local Msgs Sent                        55            55
Distr Msgs Sent                         0             0
Local Msgs Recv'd                      55            55
Distr Msgs Recv'd                       0             0
11 rows selected.
Is it normal ? It is not supposed to be supported on Oracle 11g with non-partitioned table containing LOB column....
Thank you for your help.
Michael

Yes I did it. I tried with force parallel dml, and that is the results on my 12c DB, with the non partitionned and SecureFiles LOB column.
SQL> explain plan for delete from t1;
Explained.
| Id | Operation             | Name     | Rows | Cost (%CPU)| Time     |    TQ |IN-OUT| PQ Distrib |
|   0 | DELETE STATEMENT      |          |     4 |     2   (0)| 00:00:01 |        |      |            |
|   1 | DELETE               | T1       |       |            |          |        |      |            |
|   2 |   PX COORDINATOR      |          |       |            |          |        |      |            |
|   3 |    PX SEND QC (RANDOM)| :TQ10000 |     4 |     2   (0)| 00:00:01 | Q1,00 | P->S | QC (RAND) |
|   4 |     PX BLOCK ITERATOR |          |     4 |     2   (0)| 00:00:01 | Q1,00 | PCWC |            |
|   5 |      TABLE ACCESS FULL| T1       |     4 |     2   (0)| 00:00:01 | Q1,00 | PCWP |            |
The DELETE is not performed in Parallel.
I tried with another statement :
SQL> explain plan for
2        insert into t1 select * from t1;
Here are the results:
11g
| Id | Operation                | Name     | Rows | Bytes | Cost (%CPU)| Time     |    TQ |IN-OUT| PQ Distrib |
|   0 | INSERT STATEMENT         |          |     4 | 8008 |     2   (0)| 00:00:01 |        |      |            |
|   1 | LOAD TABLE CONVENTIONAL | T1       |       |       |            |          |        |      |            |
|   2 |   PX COORDINATOR         |          |       |       |            |          |        |      |            |
|   3 |    PX SEND QC (RANDOM)   | :TQ10000 |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | P->S | QC (RAND) |
|   4 |     PX BLOCK ITERATOR    |          |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | PCWC |            |
|   5 |      TABLE ACCESS FULL   | T1       |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | PCWP |            |
12c
| Id | Operation                          | Name     | Rows | Bytes | Cost (%CPU)| Time     |    TQ |IN-OUT| PQ Distrib |
|   0 | INSERT STATEMENT                   |          |     4 | 8008 |     2   (0)| 00:00:01 |        |      |            |
|   1 | PX COORDINATOR                    |          |       |       |            |          |        |      |            |
|   2 |   PX SEND QC (RANDOM)              | :TQ10000 |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | P->S | QC (RAND) |
|   3 |    LOAD AS SELECT                  | T1       |       |       |            |          | Q1,00 | PCWP |            |
|   4 |     OPTIMIZER STATISTICS GATHERING |          |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | PCWP |            |
|   5 |      PX BLOCK ITERATOR             |          |     4 | 8008 |     2   (0)| 00:00:01 | Q1,00 | PCWC |            |
It seems that the DELETE statement has problems but not the INSERT AS SELECT !

Insert statement does not insert all records from a partitioned table

Hi
I need to insert records in to a table from a partitioned table.I set up a job and to my surprise i found that the insert statement is not inserting all the records on the partitioned table.
for example when i am using select statement on to a partitioned table
it gives me 400 records but when i insert it gives me only 100 records.
can anyone help in this matter.

INSERT INTO TABLENAME(COLUMNS)
(SELECT *
FROM SCHEMA1.TABLENAME1
JOIN SCHEMA2.TABLENAME2a
ON CONDITION
JOIN SCHEMA2.TABLENAME2 b
ON CONDITION AND CONDITION
WHERE CONDITION
AND CONDITION
AND CONDITION
AND CONDITION
AND (CONDITION
HAVING SUM(COLUMN) > 0
GROUP BY COLUMNS

Does sql server could export a partition from a partition table ?

Dear :
Does sql server could export a partition from a partition table ?
For example, I need to export all old partition,which is '2013' and drop them. It is easy in oracle. but how to do with sql
server 2012 ?

where do you want it to be exported to? Another server instance? if yes you can do piecemeal restore if partition is in a separate filegroup and you're on full recovery model
http://msdn.microsoft.com/en-IN/library/ms177425.aspx
Please Mark This As Answer if it helps to solve the issue Visakh ---------------------------- http://visakhm.blogspot.com/ https://www.facebook.com/VmBlogs

How to exp a specific partition data from a partitioned table

Thanks in advance.
Is is possible to export a specific partition data from a partitioned table? If so Please describe how with an example. Thank You.

You would specify a partition with the table_name:partition_name syntax at the TABLES parameter.
See examples at
http://download.oracle.com/docs/cd/B19306_01/server.102/b14215/exp_imp.htm#CEGCJABJ

Import data from a partitioned table

I am trying to import data from another server database. I need only data from two partitions from a partitioned table in that database. I have to use IMPORT wizard.
The new server should also have the partitioned table with those two partitions data.

I created the database on the destination server with a primary, log, FG1 and FG2 filegroups.
Next, created the partition function and scheme
create partition function pfOrders(int)
as range right
for values(34);
create partition scheme psOrders
as partition pfOrders
to (FG1,FG2)
go
Next, created the table on primary with primary key.
Next, used import wizard twice to import data related to partition_id 34 and 65.
The problem is the data is on primary filegroup. FG1 and FG2 does not have any data.

[SOLVED] UEFI system booting from MBR partition table and GRUB legacy

I'm trying to understand once and for all the process by which Arch can be booted from a system with UEFI firmware and an MBR partition table. Some of the information on the wiki seems conflictual / non-nonsensical at times. Apologies in advance if this has been answered time and time again, but I did search around and all I found was fixes to get Arch to boot rather than comprehensive explanations of the boot process.
Now, the way I would imagine it works is that it's just completely identical to the way it would work with a BIOS firmware. The UEFI firmware detects an MBR partitioning scheme (or is configured to know it's an MBR partitioning scheme), activates some "legacy" mode and executes the MBR boot code, just like a BIOS firmware would.
The wiki however, says different. From the Macbook article: "Do not install GRUB onto /dev/sda !!! Doing so is likely to lead to an unstable post-environment."?
So what is there in the MBR boot sector? Nothing?
How does the firmware know what to boot if there's no 0xEF BIOS boot partition and no Grub stage 1 in the MBR boot sector?
Also, how does installing Grub stage 1 to a partition work? Does it have to be at the beginning of the partition? Wouldn't that overwrite some existing data?
I'm especially puzzled since many guides to installing Vista on a macbook recommend simply formatting as MBR, and installing as normal, which I suppose entails having the Windows installation process write its boot code to the MBR, ie the equivalent of installing grub stage 1 to /dev/sda rather than to the /boot partition, as the Macbook article suggests.
Any input is appreciated.
P.S. I realize it's probably simpler, if I just want to dual boot Windows and Arch, to install Windows 7 in UEFI-GPT mode, let it create the EFI System Partition, and then install GRUB 2 to that partition, but I'm still curious about the UEFI-MBR boot process.
Last edited by padavoine (2012-06-06 09:35:10)

padavoine wrote:
CSM in UEFI firmwares do the exact same job as normal BIOS firmware.
So it's something specific to the Mac that it's able to boot from a partition's VBR while ignoring the MBR?
The reason that warning is given is because grub-legacy modifies more than just the MBR boot code region. It can overwrite some parts of GPT header.
Not true, the instruction is given in the context of an MBR format, not in the context of a GPT format, so there's nothing to overwrite and Stage 1.5 should be safely embeddable in the post-MBR gap.
In BIOS boot (normal case in non-UEFI firmwares or CSM in UEFI firmwares) does not read the partitition table (atleast it is supposed to be dumb in this regard), it simply launches whatever boot code exists in the 1st 440-byte of the MBR region.
So again, you're saying it's specific to the Mac UEFI that it lets you choose a partition whose VBR to load, regardless of what's in the MBR?
I haven't used Macs so I can't comment on Mac firmware behaviour. But normal BIOS firmwares (legacy and CSM) launch only the MBR boot code and not the partition boot code. We need some chainload capable boot manager in the MBR to launch the partition VBR.
grub-legacy does not know anything about GPT. So when you install grub-legacy to /dev/sda, it install the MBR boot code (stage1) and stage 1.5 code to the (supposed) post MBR gap. Since there is no actual post MBR gap in GPT (which has been taken over by the header and partition table), grub-legacy does not check for GPT and it assumes the post MBR gap actually exists which is invalid in case of GPT. grub-legacy embeds the stage 1.5 code in GPT header and table region (which grub assumes to be unused post MBR gap) and thus corrupts it.
0xEF is the MBR type code for UEFISYS partition. grub stage 1 (used in grub-legacy, not in grub2) is the 440-byte boot code stored in MBR for use in BIOS boot.
That's precisely my point: with neither proper executable code in the MBR (since grub was installed to a partition, not to the MBR) nor a UEFI system partition, what does the firmware default to, and how does it know what partition to boot from?
In that case it might fallback to UEFI Shell (if it exists) or give an error similar to the case where BIOS does not find any bootable code in 440-byte MBR region.
So even with bootcamp/CSM, the disk also needs to be MBR partitioned. So Macs use something called "Hybrid GPT/MBR" ( http://rodsbooks.com/gdisk/hybrid.html ) where the MBR table is synced to match the first 3 partitions in the GPT table.
I know what Bootcamp does, and that's not what I was referring to. I was referring to standalone Vista installs. I wasn't puzzled at the fact that they were using MBR, I was puzzled at the fact that contrary to the recommendations for the standalone Arch install on the wiki (with MBR partitioning, not GPT), they didn't do anything to try and prevent Windows from writing to the MBR.
You can't prevent Windows from overwriting the MBR region. You have to re-install the bootloader (grub2/syslinux etc.) after installing Windows. That is the reason why it is recommended to install Windows first and linux later.
Thats not true. I actually find it is much easier to install Windows UEFI-GPT using USB rather than a DVD.
I haven't done it since the only UEFI system I own has no DVD drive, but I was under the impression that it was simply a matter of choosing DVD UEFI boot in the firmware's boot menu.
format the USB as FAT32 and extract the iso to it. That it.
No, thats not it, precisely, it doesn't work out of the box with a standard Windows install USB, you need to fiddle around:
2.3 Extract bootmgfw.efi from [WINDOWS_x86_64_ISO]/sources/install.wim => [INSTALL.WIM]/1/Windows/Boot/EFI/bootmgfw.efi (using 7-zip aka p7zip for both the files), or copy it from C:\Windows\Boot\EFI\bootmgfw.efi from a working Windows x86_64 installation.
2.4 Copy the extracted bootmgfw.efi file to [MOUNTPOINT]/efi/microsoft/boot/bootmgfw.efi .
Most of the Windows isos already have /EFI/BOOT/BOOTX64.EFI file, so no need to extract the bootmgfw.efi file.
There is no difference between in BIOS booting in UEFI firmwares and BIOS booting with legacy firmware.
There has to be a difference, at least in the Mac firmware (sorry, I keep switching), since legacy firmware, AFAIK, cannot chainload a bootloader in a partition's VBR without there being some sort of "stage1" code in the MBR.
No idea about Mac EFI. Apple made a spagetti out of UEFI Spec. To actually understand how Mac firmwares work, read the blog posts by Matthew Garrett of Redhat, about his efforts in getting Fedora to boot in Macs.

Gathering statistics on partitioned and non-partitioned tables

Hi all,
My DB is 11.1
I find that gathering statistics on partitioned tables are really slow.
TABLE_NAME                       NUM_ROWS     BLOCKS SAMPLE_SIZE LAST_ANALYZED PARTITIONED COMPRESSION
O_FCT_BP1                        112123170     843140    11212317 8/30/2011 3:5            NO                    DISABLED
LEON_123456                      112096060     521984    11209606 8/30/2011 4:2           NO                   ENABLED
O_FCT                           115170000     486556      115170 8/29/2011 6:3            YES
SQL> SELECT COUNT(*) FROM user_tab_subpartitions
2 WHERE table_name =O_FCT'
3 ;
COUNT(*)
       112I used the following script:
BEGIN
DBMS_STATS.GATHER_TABLE_STATS(ownname          => user,
                                tabname          => O_FCT',
                                method_opt       => 'for all columns size auto',
                                degree           => 4,
                                estimate_percent =>10,
                                granularity      => 'ALL',
                                cascade          => false);
END;
/It costs 2 mins for the first two tables to gather the statistics respectively, but more than 10 mins for the partitioned table.
The time of collecting statistics accounts for a large part of total batch time.
And most jobs of the batch are full load in which case all partitions and subpartitions will be affected and we can't just gather specified partitions.
Does anyone have some experiences on this subject? Thank you very much.
Best regards,
Leon
Edited by: user12064076 on Aug 30, 2011 1:45 AM

Hi Leon
Why don't you gather stats at partition level? If your partitions data is not going to change after a day (date range partition for ex), you can simply do at partition level
GRANULARITY=>'PARTITION' for partition level and
GRANULARITY=>'SUBPARTITION' for subpartition level
You are gathering global stats every time which you may not require.
Edited by: user12035575 on 30-Aug-2011 01:50

Archiving old data from a partitioned table

Hi,
While sifting through all the options for archiving the old data from a table which is also indexed, i came across a few methods which could be used:
1. Use a CTAS to create new tables on a different tablespace from the partitions on the exisitng table. Then swap these new tables with the data from the partitions, drop the partitions on the exisiting table (or truncate them although i m not sure which one is the recommended method),offline this tablespace and keep it archived. In case you require it in the future, again swap these partitions wih the data from the archived tables. I am not sure if i got the method correctly.
2. Keep an export of all the partitions which need to be archived and keep that .dmp file on a storage media. Once they are exported, truncate the corresponding partitions in the original table. If required in the future, import these partitions.
But i have one constraint on my Db which is I cannot create a new archive tablespace for holding the tables containing the partitioned data into then as I have only 1 tablespace allocated to my appplication on that DB as there are multiple apps residing on it together. Kindly suggest what option is the best suited for me now. Should I go with option 2?
Thanks in advance.

Hi,
Thanks a bunch for all your replies. Yeah, I am planning to go ahead with the option 2. Below is the method I have decided upon. Kindly verify is my line of understanding is correct:
1. export the partition using the clause:
exp ID/passwd file=abc.dmp log=abc.log tables=schemaname.tablename:partition_name rows=yes indexes=yes
2. Then drop this partition on the original table using the statement:
ALTER TABLE tablename drop PARTITION partition_name UPDATE GLOBAL INDEXES;
If I now want to import this dump file into my original table again, I will first have to create this partition on my table using the statement:
3. ALTER TABLE tablename ADD PARTITION partition_name VALUES LESS THAN ( '<<>>' ) ;
4. Then import the data into that partition using:
imp ID/passwd FILE=abc.dmp log=xyz.log TABLES=schemaname.tablename:partition_name IGNORE=y
Now my query here is that this partitioned table has a global index associated with it. So once i create this partition and import the data into it, do i need to drop and recreate the global indexes on this table or is there any aother method to update the indexes. Kindly suggest.
Thanks again!! :)

Converting from non partitioned to partitioned table

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