133 DBMS_REDEFINITION

The DBMS_REDEFINITION package provides an interface to perform an online redefinition of tables.

This chapter contains the following topics:

See Also:

Oracle Database Administrator's Guide for more information about online redefinition of tables

133.1 DBMS_REDEFINITION Overview

To achieve online redefinition, incrementally maintainable local materialized views are used. These logs keep track of the changes to the master tables and are used by the materialized views during refresh synchronization.

133.2 DBMS_REDEFINITION Security Model

Subprograms in the DBMS_REDEFINITION package are run with invokers' rights (with the privileges of the current user).

There are two modes:

  • In USER mode, the user who has the CREATE TABLE and CREATE MVIEW privileges may redefine a table residing in his own schema.

  • In FULL mode, the user who has the ANY privilege may redefine tables in any schema.

133.3 DBMS_REDEFINITION Constants

The DBMS_REDEFINITION package defines several constants for specifying parameter values.

Table 133-1 DBMS_REDEFINITION Constants

Constant Type Value Description

CONS_CONSTRAINT

PLS_INTEGER

3

Used to specify that dependent object type is a constraint

CONS_INDEX

PLS_INTEGER

2

Used to specify that dependent object type is a index

CONS_MVLOG

PLS_INTEGER

10

Used to (un)register a materialized view log, as a dependent object of the table, through the REGISTER_DEPENDENT_OBJECT Procedureand the UNREGISTER_DEPENDENT_OBJECT Procedure.

CONS_ORIG_PARAMS

PLS_INTEGER

1

Used to specify that indexes should be cloned with their original storage parameters

CONS_TRIGGER

PLS_INTEGER

4

Used to specify that dependent object type is a trigger

CONS_USE_PK

BINARY_INTEGER

1

Used to indicate that the redefinition should be done using primary keys or pseudo-primary keys (unique keys with all component columns having not-NULL constraints)

CONS_USE_ROWID

BINARY_INTEGER

2

Used to indicate that the redefinition should be done using rowids

CONS_VPD_AUTO

BINARY_INTEGER

2

Used to indicate to copy VPD policies automatically

CONS_VPD_MANUAL

BINARY_INTEGER

4

Used to indicate to copy VPD policies manually

CONS_VPD_NONE

BINARY_INTEGER

1

Used to indicate that there are no VPD policies on the original table

133.4 DBMS_REDEFINITION Operational Notes

The following operational notes apply to DBMS_REDEFINITION.

  • CONS_USE_PK and CONS_USE_ROWID are constants used as input to the "options_flag" parameter in both the START_REDEF_TABLE Procedure and CAN_REDEF_TABLE Procedure. CONS_USE_ROWID is used to indicate that the redefinition should be done using rowids while CONS_USE_PK implies that the redefinition should be done using primary keys or pseudo-primary keys (which are unique keys with all component columns having NOT NULL constraints).

  • CONS_INDEX, CONS_MVLOG,CONS_TRIGGER and CONS_CONSTRAINT are used to specify the type of the dependent object being (un)registered in REGISTER_DEPENDENT_OBJECT Procedure and UNREGISTER_DEPENDENT_OBJECT Procedure (parameter "dep_type").

    CONS_INDEX ==> dependent object is of type INDEX

    CONS_TRIGGER ==> dependent object is of type TRIGGER

    CONS_CONSTRAINT==> dependent object type is of type CONSTRAINT

    CONS_MVLOG ==> dependent object is of type MATERIALIZED VIEW LOG

  • CONS_ORIG_PARAMS as used as input to the "copy_indexes" parameter in COPY_TABLE_DEPENDENTS Procedure. Using this parameter implies that the indexes on the original table be copied onto the interim table using the same storage parameters as that of the original index.

133.5 DBMS_REDEFINITION Rules and Limits

Various rules and limits apply to implementation of the DBMS_REDEFINITION package.

For more information about these, see the Oracle Database Administrator's Guide.

133.6 DBMS_REDEFINITION Examples

The following examples demonstrate DBMS_REDEFINITION functionality.

We create two tables EMP and EMP_INT as the original and the interim tables, respectively:

CREATE TABLE "EMP"
( "EMPNO" NUMBER(4,0) PRIMARY KEY,
"ENAME" VARCHAR2(10),
"JOB" VARCHAR2(9),
"MGR" NUMBER(4,0),
"HIREDATE" DATE,
"SAL" NUMBER(7,2),
"COMM" NUMBER(7,2),
"DEPTNO" NUMBER(2,0)) 

TABLESPACE myts;

CREATE TABLE "EMP_INT"
( "EMPNO" NUMBER(4,0) PRIMARY KEY,
"ENAME" VARCHAR2(10),
"JOB" VARCHAR2(9),
"MGR" NUMBER(4,0),
"HIREDATE" DATE,
"SAL" NUMBER(7,2),
"COMM" NUMBER(7,2),
"DEPTNO" NUMBER(2,0)) 

TABLESPACE compressed_ts;

Regular Multi-Step Redefinition

DBMS_REDEFINITION.START_REDEF_TABLE(‘SCOTT’, ‘EMP’, ‘EMP_INT’, ENABLE_ROLLBACK => TRUE);
DBMS_REDEFINITION.FINISH_REDEF_TABLE(‘SCOTT’, ‘EMP’, ‘EMP_INT’);

Assume theDBA wants to evaluate the performance of the application for 2 days, after moving the table EMP from tablespace myts to compressed_ts. One can run sync_interim_table SYNC_INTERIM_TABLE Procedureto keep both the tables in sync (say, every hour).

DBMS_REDEFINITION.SYNC_INTERIM_TABLE(‘SCOTT’, ‘EMP’, ‘EMP_INT’);

Case 1 — DBA is not happy with the performance, so decides to rollback.

DBMS_REDEFINITION.ROLLBACK(‘SCOTT’, ‘EMP’, ‘EMP_INT’);

Case 2 — DBA is happy with the performance, so decides not to rollback.

DBMS_REDEFINITION.ABORT_ROLLBACK(‘SCOTT’, ‘EMP’, ‘EMP_INT’);

This terminates the possibility of rollback.

Single-Step Redefinition

DBMS_REDEFINITION.REDEF_TABLE(’SCOTT’,’EMP’,'ROW STORE COMPRESS ADVANCED', enable_rollback => TRUE);

Note:

Online table redefinition rollback is not supported when the REDEF_TABLE procedure is used to redefine a table.

133.7 Summary of DBMS_REDEFINITION Subprograms

This table lists the DBMS_REDEFINITION subprograms and briefly describes them.

Table 133-2 DBMS_REDEFINITION Package Subprograms

Subprogram Description

ABORT_REDEF_TABLE Procedure

Cleans up errors that occur during the redefinition process and removes all temporary objects created by the reorganization process

ABORT_ROLLBACK Procedure

Aborts rollback

ABORT_UPDATE Procedure

Aborts an update started with the EXECUTE_UPDATE procedure

CAN_REDEF_TABLE Procedure

Determines if a given table can be redefined online

COPY_TABLE_DEPENDENTS Procedure

Copies the dependent objects of the original table onto the interim table

EXECUTE_UPDATE Procedure

Optimizes the performance of bulk updates to a table

FINISH_REDEF_TABLE Procedure

Completes the redefinition process

REDEF_TABLE Procedure

Provides a single push-button interface that integrates several redefinition steps

REGISTER_DEPENDENT_OBJECT Procedure

Registers a dependent object (index, trigger, constraint or materialized view log) on the table being redefined and the corresponding dependent object on the interim table

ROLLBACK Procedure

Performs rollback

SET_PARAM Procedure

Sets a new value for a specified parameter used by the redefinition process identified by a redefinition ID

START_REDEF_TABLE Procedure

Initiates the redefinition process

SYNC_INTERIM_TABLE Procedure

Keeps the interim table synchronized with the original table

UNREGISTER_DEPENDENT_OBJECT Procedure

Unregisters a dependent object (index, trigger, constraint or materialized view log) on the table being redefined and the corresponding dependent object on the interim table

133.7.1 ABORT_REDEF_TABLE Procedure

This procedure cleans up errors that occur during the redefinition process.

This procedure can also be used to terminate the redefinition process any time after the START_REDEF_TABLE Procedure has been called and before the FINISH_REDEF_TABLE Procedure is called. This process will remove the temporary objects that are created by the redefinition process such as materialized view logs.

Syntax

DBMS_REDEFINITION.ABORT_REDEF_TABLE (
   uname                   IN  VARCHAR2,
   orig_table              IN  VARCHAR2,
   int_table               IN  VARCHAR2,
   part_name               IN  VARCHAR2 := NULL);

Parameters

Table 133-3 ABORT_REDEF_TABLE Procedure Parameters

Parameter Description

uname

Schema name of the tables

orig_table

Name of the table to be redefined

int_table

Name of the interim table. Can take a comma-delimited list of interim table names.

part_name

Name of the partition being redefined. If redefining only a single partition of a table, specify the partition name in this parameter. NULL implies the entire table is being redefined. Can take a comma-delimited list of partition names to be redefined.

133.7.2 ABORT_ROLLBACK Procedure

This procedure aborts rollback for a table that was redefined.

When online redefinition of a table is started with the START_REDEF_TABLE procedure, rollback can be enabled for the changes performed by online redefinition of a table by setting the enable_rollback parameter to TRUE. If you want to retain the changes made by online redefinition, you can abort the rollback to clean up the database objects that enable rollback.

Syntax

DBMS_REDEFINITION.ABORT_ROLLBACK (
   uname           IN  VARCHAR2,
   orig_table      IN  VARCHAR2,
   int_table       IN  VARCHAR2 := NULL,
   part_name       IN  VARCHAR2 := NULL);

Parameters

Table 133-4 ABORT_ROLLBACK Procedure Parameters

Parameter Description

uname

Schema name of the tables

orig_table

Name of the table to be redefined

int_table

Name of the interim table

part_name

Name of the partition being redefined

133.7.3 ABORT_UPDATE Procedure

This procedure can aborts an update started with the EXECUTE_UPDATE procedure in the RDBMS_REDEFINITION package.

Syntax

DBMS_REDEFINITION.ABORT_UPDATE (
   update_stmt  IN  CLOB); 

Parameters

Table 133-5 ABORT_UPDATE Procedure Parameters

Parameter Description

update_stmt

The SQL UPDATE statement to be aborted

The SQL statement must exactly match the SQL statement in the EXECUTE_UPDATE procedure.

133.7.4 CAN_REDEF_TABLE Procedure

This procedure determines if a given table can be redefined online. This is the first step of the online redefinition process. If the table is not a candidate for online redefinition, an error message is raised.

Syntax

DBMS_REDEFINITION.CAN_REDEF_TABLE (
   uname         IN  VARCHAR2,
   tname        IN  VARCHAR2,
   options_flag  IN  PLS_INTEGER := 1,
   part_name     IN  VARCHAR2 := NULL);

Parameters

Table 133-6 CAN_REDEF_TABLE Procedure Parameters

Parameter Description

uname

Schema name of the table

tname

Name of the table to be re-organized

options_flag

Indicates the type of redefinition method to use.

  • If dbms_redefinition.cons_use_pk, the redefinition is done using primary keys or pseudo-primary keys (unique keys with all component columns having NOT NULL constraints). The default method of redefinition is using primary keys.

  • If dbms_redefinition.cons_use_rowid, the redefinition is done using rowids.

part_name

Name of the partition being redefined. If redefining only a single partition of a table, specify the partition name in this parameter. NULL implies the entire table is being redefined.

Exceptions

If the table is not a candidate for online redefinition, an error message is raised.

133.7.5 COPY_TABLE_DEPENDENTS Procedure

This procedure clones the dependent objects of the table being redefined onto the interim table and registers the dependent objects. This procedure does not clone the already registered dependent objects.

This subprogram is used to clone the dependent objects like grants, triggers, constraints and privileges from the table being redefined to the interim table (which represents the post-redefinition table).

Syntax

DBMS_REDEFINITION.COPY_TABLE_DEPENDENTS(
   uname                    IN  VARCHAR2,
   orig_table               IN  VARCHAR2,
   int_table                IN  VARCHAR2,
   copy_indexes             IN  PLS_INTEGER := 1,
   copy_triggers            IN  BOOLEAN     := TRUE,
   copy_constraints         IN  BOOLEAN     := TRUE,
   copy_privileges          IN  BOOLEAN     := TRUE,
   ignore_errors            IN  BOOLEAN     := FALSE,
   num_errors               OUT PLS_INTEGER,
   copy_statistics          IN  BOOLEAN     := FALSE, 
   copy_mvlog               IN  BOOLEAN     := FALSE); 

Parameters

Table 133-7 COPY_TABLE_DEPENDENTS Procedure Parameters

Parameter Description

uname

Schema name of the tables

orig_table

Name of the table being redefined

int_table

Name of the interim table

copy_indexes

Flag indicating whether to copy the indexes

  • 0 - do not copy any index

  • dbms_redefinition.cons_orig_params – copy the indexes using the physical parameters of the source indexes

copy_triggers

TRUE = clone triggers, FALSE = do nothing

copy_constraints

TRUE = clone constraints, FALSE = do nothing. If compatibility setting is 10.2 or higher, then clone CHECK and NOT NULL constraints

copy_privileges

TRUE = clone privileges, FALSE = do nothing

ignore_errors

TRUE = if an error occurs while cloning a particular dependent object, then skip that object and continue cloning other dependent objects. FALSE = that the cloning process should stop upon encountering an error.

num_errors

Number of errors that occurred while cloning dependent objects

copy_statistics

TRUE = copy statistics, FALSE = do nothing

copy_mvlog

TRUE = copy materialized view log, FALSE = do nothing

Usage Notes

  • The user must check the column num_errors before proceeding to ensure that no errors occurred during the cloning of the objects.

  • In case of an error, the user should fix the cause of the error and call the COPY_TABLE_DEPENDENTS Procedure again to clone the dependent object. Alternatively the user can manually clone the dependent object and then register the manually cloned dependent object using the REGISTER_DEPENDENT_OBJECT Procedure.

  • All cloned referential constraints involving the interim tables will be created disabled (they will be automatically enabled after the redefinition) and all triggers on interim tables will not fire till the redefinition is completed. After the redefinition is complete, the cloned objects will be renamed to the corresponding pre-redefinition names of the objects (from which they were cloned from).

  • It is the user's responsibility that the cloned dependent objects are unaffected by the redefinition. All the triggers will be cloned and it is the user's responsibility that the cloned triggers are unaffected by the redefinition.

133.7.6 EXECUTE_UPDATE Procedure

This procedure can optimize the performance of bulk updates to a table. Performance is optimized because the updates are not logged in the redo log.

The EXECUTE_UPDATE procedure automatically uses the components of online table redefinition, such an interim table, a materialized view, and a materialized view log, to enable optimized bulk updates to a table. The EXECUTE_UPDATE procedure also removes fragmentation of the affected rows and ensures that the update is atomic. If the bulk updates raise any errors, then you can use the ABORT_UPDATE procedure to undo the changes made by the EXECUTE_UPDATE procedure.

Syntax

DBMS_REDEFINITION.EXECUTE_UPDATE (
   update_stmt  IN  CLOB); 

Parameters

Table 133-8 EXECUTE_UPDATE Procedure Parameters

Parameter Description

update_stmt

The SQL UPDATE statement

133.7.7 FINISH_REDEF_TABLE Procedure

This procedure completes the redefinition process.

Before this step, you can create new indexes, triggers, grants, and constraints on the interim table. The referential constraints involving the interim table must be disabled. After completing this step, the original table is redefined with the attributes and data of the interim table. The original table is locked briefly during this procedure.

Syntax

DBMS_REDEFINITION.FINISH_REDEF_TABLE (
   uname                   IN   VARCHAR2,
   orig_table              IN   VARCHAR2,
   int_table               IN   VARCHAR2,
   part_name               IN   VARCHAR2 := NULL,
   dml_lock_timeout        IN   PLS_INTEGER := NULL,
   continue_after_errors   IN   BOOLEAN := FALSE,
   disable_rollback        IN   PLS_INTEGER := FALSE);

Parameters

Table 133-9 FINISH_REDEF_TABLE Procedure Parameters

Parameters Description

uname

Schema name of the tables

orig_table

Name of the table to be redefined

int_table

Name of the interim table. Can take a comma-delimited list of interim table names.

part_name

Name of the partition being redefined. If redefining only a single partition of a table, specify the partition name in this parameter. NULL implies the entire table is being redefined. Can take a comma-delimited list of partition names to be redefined.

dml_lock_timeout

Specifies the number of seconds the procedure waits for its required locks before failing. The permissible range of values for timeout is 0 to 1,000,000. The default is NULL (wait mode).

continue_after_errors

When redefining multiple partitions allows operation execution to continue on the next partition (applies only to batched partition redefinition).

disable_rollback

When set to TRUE, disables the rollback option if it was enabled in the START_REDEF_TABLE procedure. Specifying TRUE cleans up the database objects that enable rollback.

Examples

Wait up to 600 seconds for required locks on SH.SALES:

EXECUTE DBMS_REDEFINITION.FINISH_REDEF_TABLE (
  'SH', 'SALES', 'INT_SALES', 600);

133.7.8 REDEF_TABLE Procedure

This procedure provides a single interface that integrates several redefinition steps including the CAN_REDEF_TABLE Procedure, the START_REDEF_TABLE Procedure, the COPY_TABLE_DEPENDENTS Procedure and the FINISH_REDEF_TABLE Procedure.

This procedure can change data storage properties including tablespaces (for table, partition, subpartition, index, LOB column), compress type (for table, partition, subpartition, index, LOB column) and STORE_AS clause for the LOB column.

Syntax

DBMS_REDEFINITION.REDEF_TABLE (
   uname                       IN  VARCHAR2,
   tname                       IN  VARCHAR2,    
   table_compression_type      IN  VARCHAR2 := NULL, 
   table_part_tablespace       IN  VARCHAR2 := NULL, 
   index_key_compression_type  IN  VARCHAR2 := NULL,
   index_tablespace            IN  VARCHAR2 := NULL,
   lob_compression_type        IN  VARCHAR2 := NULL,
   lob_tablespace              IN  VARCHAR2 := NULL,
   lob_store_as                IN  VARCHAR2 := NULL,
   refresh_dep_mviews          IN  VARCHAR2 := 'N',
   dml_lock_timeout            IN  PLS_INTEGER := NULL); 

Parameters

Table 133-10 REDEF_TABLE Procedure Parameters

Parameter Description

uname

Schema name of the table

tname

Name of the table to be redefined

table_compression_type

Text string of the table compression clause. NULL means there is no change.

table_part_tablespace

Tablespace name for the entire table or partitions. NULL means there is no change.

index_key_compression_type

Text string of the compression clause for all indexes on the table. NULL means there is no change.

index_tablespace

Tablespace name for all indexes on the table. NULL means there is no change.

lob_compression_type

Text string of the compression clause for all LOBs in the entire table. NULL means there is no change.

lob_tablespace

Tablespace name for all LOBs in the table. NULL means there is no change.

lob_store_as

Specifies LOB store as 'SECUREFILE' or 'BASICFILE'. NULL means there is no change.

refresh_dep_mviews

When set to 'Y', fast refresh of dependent materialized views is performed once at the end of the redefinition operation.

dml_lock_timeout

Specifies the number of seconds the procedure waits for its required locks before failing. The permissible range of values for timeout is 0 to 1,000,000. The default is NULL (wait mode).

Examples

BEGIN
   DBMS_REDEFINITION.REDEF_TABLE(
     uname                        => 'TABOWNER2',
     tname                        => 'EMP2',
     table_compression_type       => 'ROW STORE COMPRESS ADVANCED',
     table_part_tablespace        => 'NEWTBS',
     index_key_compression_type   => 'COMPRESS 1',
     index_tablespace             => 'NEWIDXTBS',
     lob_compression_type         => 'COMPRESS HIGH',
     lob_tablespace               => 'SLOBTBS',
     lob_store_as                 => 'SECUREFILE');
END;

See Also:

Oracle Database Administrator's Guide regarding "Performing Online Redefinition with the REDEF_TABLE Procedure"

133.7.9 REGISTER_DEPENDENT_OBJECT Procedure

This procedure registers a dependent object (index, trigger, constraint or materialized view log) on the table being redefined and the corresponding dependent object on the interim table.

This can be used to have the same object on each table but with different attributes. For example: for an index, the storage and tablespace attributes could be different but the columns indexed remain the same

Syntax

DBMS_REDEFINITION.REGISTER_DEPENDENT_OBJECT(
   uname                  IN    VARCHAR2,
   orig_table             IN    VARCHAR2,
   int_table              IN    VARCHAR2,
   dep_type               IN    PLS_INTEGER,
   dep_owner              IN    VARCHAR2,
   dep_orig_name          IN    VARCHAR2,
   dep_int_name           IN    VARCHAR2);

Parameters

Table 133-11 REGISTER_DEPENDENT_OBJECT Procedure Parameters

Parameters Description

uname

Schema name of the tables

orig_table

Name of the table to be redefined

int_table

Name of the interim table

dep_type

Type of the dependent object (see Constants and Operational Notes)

dep_owner

Owner of the dependent object

dep_orig_name

Name of the original dependent object

dep_int_name

Name of the interim dependent object

Usage Notes

  • Attempting to register an already registered object will raise an error.

  • Registering a dependent object will automatically remove that object from DBA_REDEFINITION_ERRORS if an entry exists for that object.

133.7.10 ROLLBACK Procedure

This procedure rolls back changes to a table after online table redefinition to return the table to its original definition and preserve DML changes made to the table.

Syntax

DBMS_REDEFINITION.ROLLBACK (
   uname                   IN  VARCHAR2,
   orig_table              IN  VARCHAR2,
   int_table               IN  VARCHAR2 := NULL,
   part_name               IN  VARCHAR2 := NULL,
   dml_lock_timeout        IN  PLS_INTEGER := NULL,
   continue_after_errors   IN  BOOLEAN := FALSE);

Parameters

Table 133-12 ROLLBACK Procedure Parameters

Parameter Description

uname

Schema name of the table to be redefined

orig_table

Name of the table to be redefined

int_table

Name of the interim table.

part_name

Name of the partition being redefined.

dml_lock_timeout

Specifies the number of seconds the procedure waits for its required locks before failing. The permissible range of values for timeout is 0 to 1,000,000. The default is NULL (wait mode).

continue_after_errors

When rolling back redefinition changes on multiple partitions, allows operation execution to continue on the next partition (applies only to batched partition redefinition).

133.7.11 SET_PARAM Procedure

This procedure sets a new value for a specified parameter used by the redefinition process identified by a redefinition ID.

Note:

Currently, the only value that can be changed by this procedure is the value for the of the refresh_dep_mviews parameter that is specified in the REDEF_TABLE procedure or the START_REDEF_TABLE procedure. You can determine the redefinition ID and check the value of the refresh_dep_mviews parameter for an online table redefinition operation by querying the DBA_REDEFINITION_STATUS view.

Syntax

DBMS_REDEFINITION.SET_PARAM (
   redefinition_id  IN  VARCHAR2,
   param_name       IN  VARCHAR2,
   param_value      IN  VARCHAR2); 

Parameters

Table 133-13 SET_PARAM Procedure Parameters

Parameter Description

redefinition_id

The redefinition ID that identifies the redefinition process

param_name

The parameter name

param_value

The new parameter value

133.7.12 START_REDEF_TABLE Procedure

This procedure starts a table redefinition.

Prior to calling this procedure, you must manually create an empty interim table (in the same schema as the table to be redefined) with the desired attributes of the post-redefinition table, and then call this procedure to initiate the redefinition.

Syntax

DBMS_REDEFINITION.START_REDEF_TABLE (
   uname                   IN  VARCHAR2,
   orig_table              IN  VARCHAR2,
   int_table               IN  VARCHAR2,
   col_mapping             IN  VARCHAR2 := NULL,
   options_flag            IN  BINARY_INTEGER := 1,
   orderby_cols            IN  VARCHAR2 := NULL,
   part_name               IN  VARCHAR2 := NULL,
   continue_after_errors   IN  BOOLEAN := FALSE,    
   copy_vpd_opt            IN  BINARY_INTEGER := CONS_VPD_NONE,
   refresh_dep_mviews      IN  VARCHAR2 := 'N',
   enable_rollback         IN  BOOLEAN := FALSE);

Parameters

Table 133-14 START_REDEF_TABLE Procedure Parameters

Parameter Description

uname

Schema name of the tables

orig_table

Name of the table to be redefined

int_table

Name of the interim table. Can take a comma-delimited list of interim table names.

col_mapping

Mapping information from the columns in the original table to the columns in the interim table. (This is similar to the column list on the SELECT clause of a query.) If NULL, all the columns in the original table are selected and have the same name after redefinition.

options_flag

Indicates the type of redefinition method to use:

  • If dbms_redefinition.cons_use_pk, the redefinition is done using primary keys or pseudo-primary keys (unique keys with all component columns having NOT NULL constraints). The default method of redefinition is using primary keys.

  • If dbms_redefinition.cons_use_rowid, the redefinition is done using rowids.

orderby_cols

This optional parameter accepts the list of columns (along with the optional keyword(s) ascending/descending) with which to order by the rows during the initial instantiation of the interim table (the order by is only done for the initial instantiation and not for subsequent synchronizations)

part_name

Name of the partition being redefined. If redefining only a single partition of a table, specify the partition name in this parameter. NULL implies the entire table is being redefined. Can take a comma-delimited list of partition names to be redefined.

continue_after_errors

When redefining multiple partitions allows operation execution to continue on the next partition (applies only to batched partition redefinition)

copy_vpd_opt

Specifies how VPD policies are handled in online redefinition

refresh_dep_mviews

When set to 'Y', fast refresh of dependent materialized views is performed when the START_REDEF_TABLE procedure is run, each time the SYNC_INTERIM_TABLE procedure is run, and when the FINISH_REDEF_TABLE procedure is run.

enable_rollback

When set to TRUE, enables the rollback option.

When this parameter is set to true, Oracle Database maintains the interim table created during redefinition after redefinition is complete. You can run the SYNC_INTERIM_TABLE procedure to synchronize the interim table periodically to apply DML changes made to the redefined table to the interim table. An internal materialized view and materialized view log enables maintenance of the interim table. If you decide to roll back the online table redefinition with the ROLLBACK procedure, then the interim table is synchronized, and Oracle Database switches back to it so that the table has its original definition.

Examples

Start redefinition of three partitions (sal03q1,sal03q2,sal03q3) in table 'STEVE.salestable' using three interim tables of int_salestable1, int_salestable2 and int_salestable3, respectively. The operation will continue on sal03q3 even if it fails on sal03q1.

DBMS_REDEFINITION.START_REDEF_TABLE(
   uname                 => 'STEVE',
   orig_table            => 'salestable',
   int_table             => 'int_salestable1, int_salestable2, int_salestable3',
   col_mapping           => NULL,
   options_flag          => DBMS_REDEFINITION.CONS_USE_ROWID,
   part_name             => 'sal03q1,sal03q2,sal03q3',
   continue_after_errors => TRUE);

Specify to copy VPD policies automatically:

EXECUTE DBMS_REDEFINITION.START_REDEF_TABLE (
  uname                  => 'SCOTT',
  orig_table             => 'T',
  int_table              => 'INT_T',
  copy_vpd_opt           => DBMS_REDEFINITION.CONS_VPD_AUTO);

133.7.13 SYNC_INTERIM_TABLE Procedure

This procedure keeps the interim table synchronized with the original table.

Syntax

DBMS_REDEFINITION.SYNC_INTERIM_TABLE (
   uname                   IN  VARCHAR2,
   orig_table              IN  VARCHAR2,
   int_table               IN  VARCHAR2,
   part_name               IN  VARCHAR2 := NULL,
   continue_after_errors   IN  BOOLEAN := FALSE);

Parameters

Table 133-15 SYNC_INTERIM_TABLE Procedure Parameters

Parameter Description

uname

Schema name of the table

orig_table

Name of the table to be redefined

int_table

Name of the interim table. Can take a comma-delimited list of interim table names.

part_name

Name of the partition being redefined. If redefining only a single partition of a table, specify the partition name in this parameter. NULL implies the entire table is being redefined. Can take a comma-delimited list of partition names to be redefined.

continue_after_errors

When redefining multiple partitions allows operation execution to continue on the next partition (applies only to batched partition redefinition)

Usage Notes

  • This step is useful in minimizing the amount of synchronization needed to be done by the FINISH_REDEF_TABLE Procedure before completing the online redefinition.

  • This procedure can be called between long running operations (such as CREATE INDEX) on the interim table to sync it up with the data in the original table and speed up subsequent operations.

133.7.14 UNREGISTER_DEPENDENT_OBJECT Procedure

This procedure unregisters a dependent object (index, trigger, constraint or materialized view log) on the table being redefined and the corresponding dependent object on the interim table.

Syntax

DBMS_REDEFINITION.UNREGISTER_DEPENDENT_OBJECT(
   uname             IN VARCHAR2,
   orig_table        IN VARCHAR2,
   int_table         IN VARCHAR2,
   dep_type          IN PLS_INTEGER,
   dep_owner         IN VARCHAR2,
   dep_orig_name     IN VARCHAR2,
   dep_int_name      IN  VARCHAR2);

Parameters

Table 133-16 UNREGISTER_DEPENDENT_OBJECT Procedure Parameters

Parameters Description

uname

Schema name of the tables

orig_table

Name of the table to be redefined

int_table

Name of the interim table

dep_type

Type of the dependent object

dep_owner

Owner of the dependent object

dep_orig_name

Name of the original dependent object

dep_int_name

Name of the interim dependent object