DBMS_RESUMABLE

136 DBMS_RESUMABLE

With the DBMS_RESUMABLE package, you can suspend large operations that run out of space or reach space limits after executing for a long time, fix the problem, and make the statement resume execution. In this way you can write applications without worrying about running into space-related errors.

This chapter contains the following topics:

136.1 DBMS_RESUMABLE Operational Notes

When you suspend a statement, you should log the suspension in the alert log. You should also register a procedure to be executed when the statement is suspended. Using a view, you can monitor the progress of the statement and indicate whether the statement is currently executing or suspended.

Suspending a statement automatically results in suspending the transaction. Thus all transactional resources are held during a statement suspend and resume. When the error condition disappears, the suspended statement automatically resumes execution. A resumable space allocation can be suspended and resumed multiple times during execution.

A suspension timeout interval is associated with resumable space allocations. A resumable space allocation that is suspended for the timeout interval (the default is two hours) wakes up and returns an exception to the user. A suspended statement may be forced to throw an exception using the DBMS_RESUMABLE.ABORT() procedure.

136.2 Summary of DBMS_RESUMABLE Subprograms

This table lists the DBMS_RESUMABLE subprograms and briefly describes them.

Table 136-1 DBMS_RESUMABLE Package Subprograms

Subprogram	Description
ABORT Procedure	Aborts a suspended resumable space allocation
GET_SESSION_TIMEOUT Function	Returns the current timeout value of the resumable space allocations for a session with `session_id`
GET_TIMEOUT Function	Returns the current timeout value of resumable space allocations for the current session
SET_SESSION_TIMEOUT Procedure	Sets the timeout of resumable space allocations for a session with `session_id`
SET_TIMEOUT Procedure	Sets the timeout of resumable space allocations for the current session
SPACE_ERROR_INFO Function	Looks for space-related errors in the error stack, otherwise returning `FALSE`

136.2.1 ABORT Procedure

This procedure aborts a suspended resumable space allocation.

The parameter session_id is the session ID in which the statement is executed. For a parallel DML/DDL, session_id is any session ID that participates in the parallel DML/DDL. This operation is guaranteed to succeed. The procedure can be called either inside or outside of the AFTER SUSPEND trigger.

Syntax

DBMS_RESUMABLE.ABORT (
   session_id  IN NUMBER);

Parameters

Table 136-2 ABORT Procedure Parameters

Parameter	Description
`session_id`	The session identifier of the resumable space allocation.

Usage Notes

To call an ABORT procedure, you must be the owner of the session with session_id, have ALTER SYSTEM privileges, or be a DBA.

136.2.2 GET_SESSION_TIMEOUT Function

This function returns the current timeout value of resumable space allocations for a session with session_id.

Syntax

DBMS_RESUMABLE.GET_SESSION_TIMEOUT (
   session_id  IN NUMBER)
RETURN NUMBER;

Parameters

Table 136-3 GET_SESSION_TIMEOUT Function Parameters

Parameter	Description
`session_id`	The session identifier of the resumable space allocation.

Return Values

Table 136-4 GET_SESSION_TIMEOUT Function Return Values

Return Value	Description
`NUMBER`	The current timeout value of resumable space allocations for a session with `session_id.`The timeout is returned in seconds.

Usage Notes

If session_id does not exist, the GET_SESSION_TIMEOUT function returns -1.

136.2.3 GET_TIMEOUT Function

This function returns the current timeout value of resumable space allocations for the current session.

Syntax

DBMS_RESUMABLE.GET_TIMEOUT
 RETURN NUMBER;

Return Values

Table 136-5 GET_TIMEOUT Function Return Values

Return Value	Description
`NUMBER`	The current timeout value of resumable space allocations for the current session. The returned value is in seconds.

Usage Notes

If the current session is not resumable enabled, the GET_TIMEOUT function returns -1.

136.2.4 SET_SESSION_TIMEOUT Procedure

This procedure sets the timeout of resumable space allocations for a session with session_id.

The new timeout setting applies to the session immediately. If session_id does not exist, no operation occurs.

Syntax

DBMS_RESUMABLE.SET_SESSION_TIMEOUT (
   session_id  IN NUMBER,
   timeout     IN NUMBER);

Parameters

Table 136-6 SET_SESSION_TIMEOUT Procedure Parameters

Parameter	Description
`session_id`	The session identifier of the resumable space allocation.
`timeout`	The timeout of the resumable space allocation.

136.2.5 SET_TIMEOUT Procedure

This procedure sets the timeout of resumable space allocations for the current session. The new timeout setting applies to the session immediately.

Syntax

DBMS_RESUMABLE.SET_TIMEOUT (
   timeout  IN NUMBER);

Parameters

Table 136-7 SET_TIMEOUT Procedure Parameters

Parameter	Description
`timeout`	The timeout of the resumable space allocation.

136.2.6 SPACE_ERROR_INFO Function

This function looks for space-related errors in the error stack.

If it cannot find a space related error, it will return FALSE. Otherwise, TRUE is returned and information about the particular object that causes the space error is returned.

Syntax

DBMS_RESUMABLE.SPACE_ERROR_INFO
   error_type        OUT VARCHAR2, 
   object_type       OUT VARCHAR2, 
   object_owner      OUT VARCHAR2, 
   table_space_name  OUT VARCHAR2, 
   object_name       OUT VARCHAR2, 
   sub_object_name   OUT VARCHAR2) 
RETURN BOOLEAN;

Parameters

Table 136-8 SPACE_ERROR_INFO Function Parameters

Parameter	Description
`error_type`	The space error type. It will be one of the following: `NO MORE SPACE` `MAX EXTENTS REACHED` `SPACE QUOTA EXCEEDED`
`object_type`	The object type. It will be one of the following: TABLE INDEX CLUSTER TABLE SPACE ROLLBACK SEGMENT UNDO SEGMENT LOB SEGMENT TEMP SEGMENT INDEX PARTITION TABLE PARTITION LOB PARTITION TABLE SUBPARTITION INDEX SUBPARTITION LOB SUBPARTITION The type can also be `NULL` if it does not apply.
`object_owner`	The owner of the object. `NULL` if it cannot be determined.
`table_space_name`	The table space where the object resides. `NULL` if it cannot be determined.
`object_name`	The name of rollback segment, temp segment, table, index, or cluster.
`sub_object_name`	The partition name or sub-partition name of `LOB, TABLE,` or `INDEX. NULL` if it cannot be determined.