1. Data archival using Partitioning and Partition Maintenance O/o the A.G.(A&E)-II NagpurMaharashtra

2. Addressing Key problems in VLC: Storage Storage Backup (Time involved) Backup (Time involved) Performance enhancement Performance enhancement Corruption of data Corruption of data

3. Approach: Two Ways: Two Ways: Delete Old data Delete Old data Partition and split partition Partition and split partition

4. Advantages/Need of Partition Do we really need partition? Do we really need partition? If we need, what Advantages we get? If we need, what Advantages we get?

5. Advantages To reduce the size of the files that needs to be backup To reduce the size of the files that needs to be backup To reduce the load on Backup To reduce the load on Backup To avoid data Corruption due to multiple tables. To avoid data Corruption due to multiple tables. Partitions can be altered, dropped, rebuild, merged and truncated. Partitions can be altered, dropped, rebuild, merged and truncated. Partitions are held & managed independently. Partitions are held & managed independently. The partitions tables can be queried and updated The partitions tables can be queried and updated

6. What is partition : “Decomposing the very large tables and indexes into smaller and more manageable pieces are called partitions” “Decomposing the very large tables and indexes into smaller and more manageable pieces are called partitions” “A single logical table can be split into number of physically separate pieces based on range of key values, each of the parts of the table is called partition” “A single logical table can be split into number of physically separate pieces based on range of key values, each of the parts of the table is called partition”

7. In what type of organization it is useful: Partitions are especially useful in data warehouse applications, which commonly Partitions are especially useful in data warehouse applications, which commonly Store and analyze large amounts of historical data. Store and analyze large amounts of historical data. i.e, VLC/GPF/Pension i.e, VLC/GPF/Pension

8. Pre_requisits Identify the tables to be partitioned on the basis of size. Identify the tables to be partitioned on the basis of size. All Partitions of a table or index have the same logical attributes. (the table share the same column and constraints definitions. All Partitions of a table or index have the same logical attributes. (the table share the same column and constraints definitions. All Partitions in an index share the same index columns. All Partitions in an index share the same index columns. The Physical attributes can be different (storage in different segments or different table space. The Physical attributes can be different (storage in different segments or different table space.

9. Partition and Split Partition: “Partition “ refers initial partition of tables, indexes. “Partition “ refers initial partition of tables, indexes. “Split partition” refers to subsequent partitions to be done in frequent intervals as decided by the user. “Split partition” refers to subsequent partitions to be done in frequent intervals as decided by the user.

10. Partition implementation in VLC It has been seen that in VLC software developed by TCS for our zone, more than 50 % of the data is associated with tables and indexes pertaining to four Tables, viz It has been seen that in VLC software developed by TCS for our zone, more than 50 % of the data is associated with tables and indexes pertaining to four Tables, viz VCHR ( Voucher table ) VCHR ( Voucher table ) VCHR_AMNT_DTL (Table storing additional attributes of voucher, amounts etc.) VCHR_AMNT_DTL (Table storing additional attributes of voucher, amounts etc.) TRSRY_ACNT_DTL (Table storing LOP/Cash Account, and the Major Head wise abstract of Compiled accounts, like PWD/IRD/FRD) TRSRY_ACNT_DTL (Table storing LOP/Cash Account, and the Major Head wise abstract of Compiled accounts, like PWD/IRD/FRD) PYMNT_CLSFD_ABSTRCT. (Table storing the posted data ) PYMNT_CLSFD_ABSTRCT. (Table storing the posted data )

11. Frequency of Splitting Partition Time based: Time based: Data Volume base: Data Volume base:

12. Steps involved in initial Partition(for Non-Partitioned table): 1. Create Two Table spaces ex: Create table space Create table space datafile ‘ datafile name’ size 600M default storage(initial 10M default storage(initial 10M Minextents 1 maxextents unlimited pctincrease 0); 2. Create temp table as select * from target table 3. Drop old table cascade constraints. 4. Create new table with partition clause. Option 1: Now, one must put in place the constraints for the table. Option 1: Now, one must put in place the constraints for the table. then insert in the data from temp table, and enable all constraints for the other table, basically FKs pointing to the target table. then insert in the data from temp table, and enable all constraints for the other table, basically FKs pointing to the target table.

13. Initial Partition Option 2 : instead of option 1, to avoid fragmentation, we can export the user Option 2 : instead of option 1, to avoid fragmentation, we can export the user (i.e, nagmain), and re importing it into the database. (i.e, nagmain), and re importing it into the database. If we go for option 2, the modified steps will be: If we go for option 2, the modified steps will be: 5. after step 4, do nothing, ie do not enable any of the constraints. after re importing the data, enable the constraints this will also ensure that the index on PK is also partitioned. 6. insert the data from temp table to original table 7. Create the indexes

14. Creatition of partitioned table Create table Create table (colm1,2,3) (colm1,2,3) Pctfree 10 Pctfree 10 Pctused 40 Pctused 40 Partition by range Partition by range (partition (partition Values less than tablespace, Values less than tablespace, (partition (partition Values less than tablespace, Values less than tablespace,

15. Steps involved in Split Partition: 1. Take a cold backup (complete) including read only files. 2. Set the tablespace containing old partition data as read-write; Syntax: Login as a dba user, and issue command: SQL> alter tablespace read write; 3. Allocate sufficient additional space in the above tablespace. 4 Resizing the data file ‘ or ‘ Adding a new data file. Adding a new data file.

16. Split Partition Syntax: Login as a dba user, and issue the commands: Syntax: Login as a dba user, and issue the commands: For resizing the file: For resizing the file: SQL> alter database datafile ‘/path/datefile name.dbf’ resize n M; SQL> alter database datafile ‘/path/datefile name.dbf’ resize n M; ex: alter database datafile ‘/home2/agnag2/txn_data01.dbf’ resize 500M; ex: alter database datafile ‘/home2/agnag2/txn_data01.dbf’ resize 500M;

17. For adding datafile: SQL> alter tablespace VLC_TXN_DATA01 add datafile ‘path/ datefile name.dbf ’ size n M; SQL> alter tablespace VLC_TXN_DATA01 add datafile ‘path/ datefile name.dbf ’ size n M; ex: alter tablespace VLC_TXN_DATA01 add datafile ‘/home2/agnag2/txn_data02.dbf’size 500M; ex: alter tablespace VLC_TXN_DATA01 add datafile ‘/home2/agnag2/txn_data02.dbf’size 500M; 5. The subsequent steps depend on the table being partitioned. (a) For VCHR (assuming split at gnrtd id of 60000 and spitting at higher end of partition vchr_P2): (a) For VCHR (assuming split at gnrtd id of 60000 and spitting at higher end of partition vchr_P2): (i) Coalesce the free space in both relevant tablespaces: (i) Coalesce the free space in both relevant tablespaces:

18. Split Partition Syntax: Syntax: SQL> alter tablespace VLC_TXN_DATA01 coalesce; SQL> alter tablespace VLC_TXN_DATA01 coalesce; SQL> alter tablespace VLC_TXN_DATA02 coalesce; SQL> alter tablespace VLC_TXN_DATA02 coalesce; (ii) Split the partition using following command : (ii) Split the partition using following command : SQL> alter table vchr split partition SQL> alter table vchr split partition vchr_p2 at (60000) into ( vchr_p2 at (60000) into ( Partition vchr_p2 tablespace vlc_txn_data01, Partition vchr_p2 tablespace vlc_txn_data01, Partition vchr_p3 tablespace vlc_txn_data02 ); Partition vchr_p3 tablespace vlc_txn_data02 );

19. split Partition (iii) Coalesce the free space in both relevant tablespaces: SQL> alter tablespace VLC_TXN_DATA01 coalesce; (iii) Coalesce the free space in both relevant tablespaces: SQL> alter tablespace VLC_TXN_DATA01 coalesce; SQL> alter tablespace VLC_TXN_DATA02 coalesce; SQL> alter tablespace VLC_TXN_DATA02 coalesce; (iv) Rebuild the indexes pertaining to the table, which are shown with status unusable in the dba view: dba_ind_partitions. The command for this can be generated by firing the query given below and spooling the output: (iv) Rebuild the indexes pertaining to the table, which are shown with status unusable in the dba view: dba_ind_partitions. The command for this can be generated by firing the query given below and spooling the output:

20. Split Partition select 'alter index '||index_name||' rebuild partition '|| partition_name||' ;' select 'alter index '||index_name||' rebuild partition '|| partition_name||' ;' from dba_ind_partitions from dba_ind_partitions where index_owner=’owner name’ ( ex: 'NAGMAIN') where index_owner=’owner name’ ( ex: 'NAGMAIN') and status='UNUSABLE'; and status='UNUSABLE';

21. Split Partition 6. Similar steps mentioned in Sr.No.5 above should be followed for other tables 7. Finally, after the partitions have been split, and data moved from tablespace current tablespace to old tablespace (ex:VLC_TXN_DATA02 to VLC_TXN_DATA01,) 8. try to resize the (ie.,VLC_TXN_DATA01) datafiles to the minimum possible.

22. Split Partition 9. Then set the old tablespace (VLC_TXN_DATA01 ) once again as read- only, and take a complete backup.

23. Thank You Thank You