Introduction 1. DBMS_REDEFINITION
- Import and Export;
- insert … select …；
- Swap zoning laws;
- Online redefinition (DBMS_REDEFINITION).
The idea of these programs is to create a new partition table, and then to transfer data from the old table to the new table top, then transfer the corresponding dependencies, and finally re-table the name, the new table the old table and rename. Compared with the previous three programs, DBMS_REDEFINITION almost does not affect the normal use of the old table, so becoming the partition table of the conversion program currently in common use.
The following project in a large table TP_CARD_INFO (about 12 million records), for example, to convert an ordinary table to illustrate the steps of the partition table.
2. Check whether the ordinary partition table
It was confirmed on a primary key:
SQL> begin
2 DBMS_REDEFINITION.CAN_REDEF_TABLE('HSADM', 'TP_CARD_INFO', Dbms_Redefinition.cons_use_pk);
3 end;
4 /
PL/SQL procedure successfully completed
No error output represents.
3. Create partition table
By primary key partitions, each no more than 2 million records:
create table TP_CARD_INFO_PART
(
id NUMBER(15) not null,
card_num VARCHAR2(32),
card_num2 VARCHAR2(32),
create_time DATE,
create_user VARCHAR2(16),
update_time DATE,
update_user VARCHAR2(16),
print_date VARCHAR2(8),
print_by NVARCHAR2(40),
print_unit_code VARCHAR2(16),
print_unit_name NVARCHAR2(70),
print_reason NVARCHAR2(40),
finger_absence NVARCHAR2(10)
)
partition by range(ID)
(
partition TP_CARD_INFO_01 values less than (2000000) tablespace HS_DAT,
partition TP_CARD_INFO_02 values less than (4000000) tablespace HS_DAT,
partition TP_CARD_INFO_03 values less than (6000000) tablespace HS_DAT,
partition TP_CARD_INFO_04 values less than (8000000) tablespace HS_DAT,
partition TP_CARD_INFO_05 values less than (10000000) tablespace HS_DAT,
partition TP_CARD_INFO_06 values less than (12000000) tablespace HS_DAT,
partition TP_CARD_INFO_99 values less than (MAXVALUE) tablespace HS_DAT
);
4. Data Migration
SQL> exec DBMS_REDEFINITION.start_redef_table('HSADM', 'TP_CARD_INFO', 'TP_CARD_INFO_PART');
PL/SQL procedure successfully completed
The whole process is 256 seconds with.
The migration permission object
SQL> declare
2 num_errors PLS_INTEGER;
3 begin
4 dbms_redefinition.copy_table_dependents('HSADM', 'TP_CARD_INFO', 'TP_CARD_INFO_PART',
5 dbms_redefinition.cons_orig_params, TRUE, TRUE, TRUE, TRUE, num_errors);
6 end;
7 /
PL/SQL procedure successfully completed
The whole process with 526 seconds.
6. Is there a wrong query
SQL> select object_name, base_table_name, ddl_txt from DBA_REDEFINITION_ERRORS;
OBJECT_NAME BASE_TABLE_NAME DDL_TXT
-------------------------------------------------------------------------------- --------------------------------------------------------------------------------
No error.
7. End redefinition process
begin
2 dbms_redefinition.finish_redef_table('HSADM', 'TP_CARD_INFO', 'TP_CARD_INFO_PART');
3 end;
4 /
PL/SQL procedure successfully completed
73 seconds the whole process.
Exit 8. When an exception occurs
If unusual redefinition process, you must perform the exit procedure:
SQL> begin
2 dbms_redefinition.abort_redef_table('HSADM', 'TP_CARD_INFO', 'TP_CARD_INFO_PART');
3 end;
4 /