DBMS_JOB, 2 of 2

Summary of Subprograms

Table 17-1 DBMS_JOB Package Subprograms

Subprogram	Description
SUBMIT Procedure	Submits a new job to the job queue.
REMOVE Procedure	Removes specified job from the job queue.
CHANGE Procedure	Alters any of the user-definable parameters associated with a job.
WHAT Procedure	Alters the job description for a specified job.
NEXT_DATE Procedure	Alters the next execution time for a specified job.
INSTANCE Procedure	Assigns a job to be run by a instance.
INTERVAL Procedure	Alters the interval between executions for a specified job.
BROKEN Procedure	Disables job execution.
RUN Procedure	Forces a specified job to run.
USER_EXPORT Procedure	Recreates a given job for export.
USER_EXPORT Procedure	Recreates a given job for export with instance affinity.

SUBMIT Procedure

This procedure submits a new job. It chooses the job from the sequence sys.jobseq.

Syntax

DBMS_JOB.SUBMIT ( 
   job       OUT BINARY_INTEGER,
   what      IN  VARCHAR2,
   next_date IN  DATE DEFAULT sysdate,
   interval  IN  VARCHAR2 DEFAULT 'null',
   no_parse  IN  BOOLEAN DEFAULT FALSE,
   instance  IN  BINARY_INTEGER DEFAULT any_instance,
   force     IN  BOOLEAN DEFAULT FALSE);

Parameters

Table 17-2 SUBMIT Procedure Parameters

Parameter	Description
job	Number of the job being run.
what	PL/SQL procedure to run.
next_date	Next date when the job will be run.
interval	Date function that calculates the next time to run the job. The default is `NULL`. This must evaluate to a either a future point in time or `NULL`.
no_parse	A flag. The default is `FALSE`. If this is set to `FALSE`, then Oracle parses the procedure associated with the job. If this is set to `TRUE`, then Oracle parses the procedure associated with the job the first time that the job is run. For example, if you want to submit a job before you have created the tables associated with the job, then set this to `TRUE`.
instance	When a job is submitted, specifies which instance can run the job.
force	If this is `TRUE`, then any positive integer is acceptable as the job instance. If this is `FALSE` (the default), then the specified instance must be running; otherwise the routine raises an exception.

Usage Notes

The parameters instance and force are added for job queue affinity. Job queue affinity gives users the ability to indicate whether a particular instance or any instance can run a submitted job.

Example

This submits a new job to the job queue. The job calls the procedure DBMS_DDL.ANALYZE_OBJECT to generate optimizer statistics for the table DQUON.ACCOUNTS. The statistics are based on a sample of half the rows of the ACCOUNTS table. The job is run every 24 hours:

VARIABLE jobno number;
BEGIN
   DBMS_JOB.SUBMIT(:jobno, 
      'dbms_ddl.analyze_object(''TABLE'',
      ''DQUON'', ''ACCOUNTS'', 
      ''ESTIMATE'', NULL, 50);' 
      SYSDATE, 'SYSDATE + 1');
   commit;
END;
/
Statement processed.
print jobno
JOBNO
----------
14144

REMOVE Procedure

This procedure removes an existing job from the job queue. This currently does not stop a running job.

Syntax

DBMS_JOB.REMOVE ( 
   job       IN  BINARY_INTEGER );

Parameters

Table 17-3 REMOVE Procedure Parameters

Parameter	Description
job	Number of the job being run.

Example

EXECUTE DBMS_JOB.REMOVE(14144);

CHANGE Procedure

This procedure changes any of the user-settable fields in a job.

Syntax

DBMS_JOB.CHANGE ( 
   job       IN  BINARY_INTEGER,
   what      IN  VARCHAR2,
   next_date IN  DATE,
   interval  IN  VARCHAR2,
   instance  IN  BINARY_INTEGER DEFAULT NULL,
   force     IN  BOOLEAN DEFAULT FALSE);

Parameters

Table 17-4 CHANGE Procedure Parameters

Parameter	Description
job	Number of the job being run.
what	PL/SQL procedure to run.
next_date	Date of the next refresh.
interval	Date function; evaluated immediately before the job starts running.
instance	When a job is submitted, specifies which instance can run the job. This defaults to `NULL`, which indicates that instance affinity is not changed.
force	If this is `FALSE`, then the specified instance (to which the instance number change) must be running. Otherwise, the routine raises an exception. If this is `TRUE`, then any positive integer is acceptable as the job instance.

Usage Notes

The parameters instance and force are added for job queue affinity. Job queue affinity gives users the ability to indicate whether a particular instance or any instance can run a submitted job.

If the parameters what, next_date, or interval are NULL, then leave that value as it is.

Example

EXECUTE DBMS_JOB.CHANGE(14144, null, null, 'sysdate+3');

WHAT Procedure

This procedure changes what an existing job does, and replaces its environment.

Syntax

DBMS_JOB.WHAT ( 
   job       IN  BINARY_INTEGER,
   what      IN  VARCHAR2);

Parameters

Table 17-5 WHAT Procedure Parameters

Parameter	Description
job	Number of the job being run.
what	PL/SQL procedure to run.

Some legal values of what (assuming the routines exist) are:

'myproc( ''10-JAN-82'', next_date, broken);'
'scott.emppackage.give_raise( ''JENKINS'', 30000.00);'
'dbms_job.remove(job);'

NEXT_DATE Procedure

This procedure changes when an existing job next runs.

Syntax

DBMS_JOB.NEXT_DATE ( 
   job       IN  BINARY_INTEGER,
   next_date IN  DATE);

Parameters

Table 17-6 NEXT_DATE Procedure Parameters

Parameter	Description
job	Number of the job being run.
next_date	Date of the next refresh: it is when the job will be automatically run, assuming there are background processes attempting to run it.

INSTANCE Procedure

This procedure changes job instance affinity.

Syntax

DBMS_JOB.INSTANCE ( 
   job        IN BINARY_INTEGER,
   instance   IN BINARY_INTEGER,
   force      IN BOOLEAN DEFAULT FALSE);

Parameters

Table 17-7 INSTANCE Procedure Parameters

Parameter	Description
job	Number of the job being run.
instance	When a job is submitted, a user can specify which instance can run the job.
force	If this is `TRUE`, then any positive integer is acceptable as the job instance. If this is `FALSE` (the default), then the specified instance must be running; otherwise the routine raises an exception.

INTERVAL Procedure

This procedure changes how often a job runs.

Syntax

DBMS_JOB.INTERVAL ( 
   job       IN  BINARY_INTEGER,
   interval  IN  VARCHAR2);

Parameters

Table 17-8 INTERVAL Procedure Parameters

Parameter	Description
job	Number of the job being run.
interval	Date function, evaluated immediately before the job starts running.

Usage Notes

If the job completes successfully, then this new date is placed in next_date. interval is evaluated by plugging it into the statement select interval into next_date from dual;

The interval parameter must evaluate to a time in the future. Legal intervals include:

'sysdate + 7'

Run once a week.

'next_day(sysdate,''TUESDAY'')'

Run once every Tuesday.

'null'

Run only once.

If interval evaluates to NULL and if a job completes successfully, then the job is automatically deleted from the queue.

BROKEN Procedure

This procedure sets the broken flag. Broken jobs are never run.

Syntax

DBMS_JOB.BROKEN ( 
   job       IN  BINARY_INTEGER,
   broken    IN  BOOLEAN,
   next_date IN  DATE DEFAULT SYSDATE);

Parameters

Table 17-9 Broken Procedure Parameters

Parameter	Description
job	Number of the job being run.
broken	Job broken: `IN` value is `FALSE`.
next_data	Date of the next refresh.

Note:
If you set job as broken while it is running, Oracle resets the job's status to normal after the job completes. Therefore, only execute this procedure for jobs that are not running.

RUN Procedure

This procedure runs job JOB now. It runs it even if it is broken.

Running the job recomputes next_date. See view user_jobs.

Syntax

DBMS_JOB.RUN ( 
   job       IN  BINARY_INTEGER,
   force     IN  BOOLEAN DEFAULT FALSE);

Parameters

Table 17-10 Run Procedure Parameters

Parameter	Description
job	Number of the job being run.
force	If this is `TRUE`, then instance affinity is irrelevant for running jobs in the foreground process. If this is `FALSE`, then the job can be run in the foreground only in the specified instance.

Example

EXECUTE DBMS_JOB.RUN(14144);

Caution:
This reinitializes the current session's packages.

Exceptions

An exception is raised if force is FALSE, and if the connected instance is the wrong one.

USER_EXPORT Procedure

This procedure produces the text of a call to recreate the given job.

Syntax

DBMS_JOB.USER_EXPORT ( 
   job    IN     BINARY_INTEGER,
   mycall IN OUT VARCHAR2);

Parameters

Table 17-11 USER_EXPORT Procedure Parameter

Parameter	Description
job	Number of the job being run.
mycall	Text of a call to recreate the given job.

USER_EXPORT Procedure

This procedure alters instance affinity (8i and above) and preserves the compatibility.

Syntax

DBMS_JOB.USER_EXPORT ( 
   job      IN     BINARY_INTEGER,
   mycall   IN OUT VARCHAR2,
   myinst   IN OUT VARCHAR2);

Parameters

Table 17-12 USER_EXPORT Procedure Parameters

Parameter	Description
job	Number of the job being run.
mycall	Text of a call to recreate a given job.
myinst	Text of a call to alter instance affinity.

Using the DBMS_JOB Package with Oracle Parallel Server

For this example, a constant in DBMS_JOB indicates "no mapping" among jobs and instances, that is, jobs can be executed by any instance.

DBMS_JOB.SUBMIT

To submit a job to the job queue, use the following syntax:

   DBMS_JOB.SUBMIT( JOB OUT BINARY_INTEGER,
   WHAT IN VARCHAR2, NEXT_DATE IN DATE DEFAULTSYSDATE, 
   INTERVAL IN VARCHAR2 DEFAULT 'NULL',
   NO_PARSE IN BOOLEAN DEFAULT FALSE,
   INSTANCE IN BINARY_INTEGER DEFAULT ANY_INSTANCE,
   FORCE IN BOOLEAN DEFAULT FALSE)

Use the parameters INSTANCE and FORCE to control job and instance affinity. The default value of INSTANCE is 0 (zero) to indicate that any instance can execute the job. To run the job on a certain instance, specify the INSTANCE value. Oracle displays error ORA-23319 if the INSTANCE value is a negative number or NULL.

The FORCE parameter defaults to FALSE. If force is TRUE, any positive integer is acceptable as the job instance. If FORCE is FALSE, the specified instance must be running, or Oracle displays error number ORA-23428.

DBMS_JOB.INSTANCE

To assign a particular instance to execute a job, use the following syntax:

   DBMS_JOB.INSTANCE(  JOB IN BINARY_INTEGER,
   INSTANCE IN BINARY_INTEGER, 
   FORCE IN BOOLEAN DEFAULT FALSE)

The FORCE parameter in this example defaults to FALSE. If the instance value is 0 (zero), job affinity is altered and any available instance can execute the job despite the value of force. If the INSTANCE value is positive and the FORCE parameter is FALSE, job affinity is altered only if the specified instance is running, or Oracle displays error ORA-23428.

If the FORCE parameter is TRUE, any positive integer is acceptable as the job instance and the job affinity is altered. Oracle displays error ORA-23319 if the INSTANCE value is negative or NULL.

DBMS_JOB.CHANGE

To alter user-definable parameters associated with a job, use the following syntax:

   DBMS_JOB.CHANGE(  JOB IN BINARY_INTEGER,
   WHAT IN VARCHAR2 DEFAULT NULL,
   NEXT_DATE IN DATE DEFAULT NULL,
   INTERVAL IN VARCHAR2 DEFAULT NULL,
   INSTANCE IN BINARY_INTEGER DEFAULT NULL,
    FORCE IN BOOLEAN DEFAULT FALSE )

Two parameters, INSTANCE and FORCE, appear in this example. The default value of INSTANCE is NULL indicating that job affinity will not change.

The default value of FORCE is FALSE. Oracle displays error ORA-23428 if the specified instance is not running and error ORA-23319 if the INSTANCE number is negative.

DBMS_JOB.RUN

The FORCE parameter for DBMS_JOB.RUN defaults to FALSE. If force is TRUE, instance affinity is irrelevant for running jobs in the foreground process. If force is FALSE, the job can run in the foreground only in the specified instance. Oracle displays error ORA-23428 if force is FALSE and the connected instance is the incorrect instance.

   DBMS_JOB.RUN( JOB IN BINARY_INTEGER,
   FORCE IN BOOLEAN DEFAULT FALSE)

`'sysdate + 7'`	Run once a week.
`'next_day(sysdate,''TUESDAY'')'`	Run once every Tuesday.
`'null'`	Run only once.