2. DBMS_SCHEDULER: The How, What and Why
David Hicken
Flying J, Inc.
Types of Users?
Level of Oracle?
OEM?
Toad?
SQL Developer?
Other tools?
PL/SQL and SQL experience?
DBA_ view experience?

3. Oracle DBMS_SCHEDULER
Scheduling Options
DBMS_Scheduler Options
Breaking Down the DBMS_SCHEDULER
Individual parts of the DBMS_SCHEDULER
Time Driven Schedules
Event Driven Schedules
DBMS_JOBS to DBMS_SCHEDULER
Monitoring the Scheduler
Things to Look Out For
Q & A

4. Oracle Scheduling Options
Cron and at in Unix and Linux
Windows Scheduler
DBMS_JOBS
Oracle Scheduler
Oracle 9i Scheduler
Oracle 10g Scheduler
Oracle 11g Scheduler

5. DBMS_Scheduler Options
Time Driven Schedules
Flexible and Easy
Event Driven Schedules
Harder to set up
Chaining Schedules
Can be used with Time or Event

6. Breaking Down DBMS_Scheduler
Programs
Schedules
Jobs
Job Classes
Windows
Window Groups
Chains

7. DBMS_SCHEDULER: Programs
Stored Procedure
Can pass parameters
PL/SQL Block
Executable
Dependent upon the OS.

9. DBMS_SCHEDULER: Schedules
Named Schedules
On the fly
Can use old DBMS_JOBS scheduling syntax, or new syntax.
EVALUATE_CALENDAR_STRING

11. DBMS_SCHEDULER Schedule words
FREQ
Yearly
Monthly
Weekly
Hourly
Minutely
Secondly
INTERVAL
Number
BYMONTH
BYDAY
BYHOUR
BYMINUTE
BYSECOND
BYWEEKNO
BYDATE
BYMONTHDAY
INCLUDE
ByMonth=May,Jun,Jul,Aug
ByHour=0,1,2,3,4,5,6,7,17,18,19,20,21,22,23
ByDay=Mon,Tue,Wed,Thu,Fri
ByWeekNo=4
ByMonthDay=3
And many others!

12. DBMS_SCHEDULER: Jobs begin dbms_scheduler.create_job (
job_name => 'HR_STATS_REFRESH',
job_type => 'PLSQL_BLOCK',
job_action => '- - Gather HR Stats
BEGIN
DBMS_STATS.GATHER_SCHEMA_STATS(''hr'');
END;',
start_date => systimestamp,
repeat_interval => 'FREQ=DAILY';byhour=9;byminute=0,
enabled => TRUE,
comments => 'Refreshes the HR Schema at 9:00 PM' );
end; /

16. DBMS_SCHEDULER: Job Classes
Create Job Class to group jobs
Assign Resources to Job Class
Control Jobs according to Class
Start and Stop a group of jobs
Set Priorities for a Job Class

18. DBMS_SCHEDULER: Windows
Caution: Windows are NOT schedules
Only one window open at a time
When windows conflict, Priority and “First Open”
Stop on Window Close
Force Windows to Open and/or Close

20. DBMS_SCHEDULER: Window Groups
Combine Windows
Weeknights
Weekends
MAINTENANCE_WINDOW

22. DBMS_SCHEDULER: Event Driven Schedules
Requires Advanced Queuing
Defined Events
More advanced than this class ....

23. DBMS_SCHEDULER Events
JOB_STARTED
JOB_SUCCEEDED
JOB_FAILED
JOB_BROKEN
JOB_COMPLETED
JOB_STOPPED
JOB_SCH_LIM_REA CHED
JOB_DISABLED
JOB_CHAIN_STALL ED
JOB_OVER_MAX_D URATION
Events raised by applications

24. DBMS_SCHEDULER: Chains
Can be Time Driven or Event Driven
Define Programs
Define Steps
A program
Another chain (nested chain)
An Event

26. Monitoring and Managing the Scheduler
Oracle Enterprise Manager
Straight forward, but many screens deep
Toad
Implemented poorly in current versions, but next version (Toad 10) is greatly improved
DBA_ Views

30. Scheduler DBA_ Views DBA_SCHEDULER_JOBS DBA_SCHEDULER_PROGRAM_A RGS
DBA_SCHEDULER_WINGROUP_ MEMBERS
DBA_SCHEDULER_SCHEDULES
DBA_SCHEDULER_WINDOWS
DBA_SCHEDULER_JOB_RUN_DE TAILS
DBA_SCHEDULER_WINDOW_DET AILS
DBA_SCHEDULER_RUNNING_JO BS
DBA_SCHEDULER_CHAIN_STEPS
DBA_QUEUE_SCHEDULES
DBA_SCHEDULER_JOB_ARGS
DBA_SCHEDULER_WINDOW_LO GDBA_SCHEDULER_RUNNING_C HAINS
DBA_SCHEDULER_GLOBAL_ATT RIBUTE
DBA_SCHEDULER_WINDOW_GR OUPS
DBA_SCHEDULER_PROGRAMS
DBA_SCHEDULER_JOB_CLASSE S
DBA_SCHEDULER_JOB_LOG
DBA_SCHEDULER_CHAIN_RULE S
DBA_SCHEDULER_CHAINS

32. Things to Watch for... OEM has trouble defining schedules
Toad's implementation is poor
Bug in creating programs. Test run script first
Uses TIMESTAMP, which has a bug prior to Makes it hard to see when schedules fire
Some of the DBA_ views may require some “tweaking” due to above bug
ALTER SYSTEM SET job_queue_processes=0; doesn't stop schedules!

33. DBMS_Scheduler vs. DBMS_Jobs
More versatile scheduling
Scheduling syntax is readable
Event driven ability
Chaining ability
Enable/Disable
Easily editable
Parameters
Logging
… and that's the ones off the top of my head.

34. Quick Comparison Feature DBMS_JOBS DBMS_Scheduler
Schedule jobs based on anonymous blocks and PL/SQL Procedures
YES
Schedule jobs on OS commands NO
Schedule recurring jobs using SYSDATE
Schedule base on an interval
YES, but complex
Schedule using calendar syntax expression
Schedule using predefined schedule
Schedule using predefined window
Modify existing job attributes
Assign Priorities to jobs

35. Quick Comparison 2 Feature DBMS_JOBS DBMS_Scheduler
Group Jobs into a Job Class NO
YES
Allow multiple jobs to share schedule
Use Oracle Resource Management to determine schedules
Limit Jobs to a single instance in a RAC configuration
Allow jobs to run on several nodes in a RAC
Full integration in Oracle Enterprise Manager
Partial
Provide privileges and roles for specifically control job scheduling
Easy to use
Easy to modify

36. Converting DBMS_JOBS to DBMS_SCHEDULER
Can use old syntax
trunc(sysdate)+1+3/24
Can use new syntax
freq=daily;interval=1;byhour=3;byminute=2 4
Caution with self-replicating DBMS_JOBS

37. DBMS_SCHEDULER The How What and Why
Questions?