SchedulerLite
User Documentation
Table of Contents
SchedulerLite - Estimated Job Runs Screen.
SchedulerLite - Logs of Job Run Times Screen.
You are the DBA whose area of responsibility covers the Scheduled jobs. You arrive at work on Monday to find that one of the Financial Directors reports has not been produced and on investigation find that the cause was that the schedule object that the job utilised had an end date that had been breached resulting in the job not running.
The previous week one of the main batch processes that run overnight overran its completion time. The cause of that problem was that one of your co-worker DBA’s had added a scheduled job without informing yourself.
Every week there is one problem or another. Stand back for one minute. The cause of your difficulties is that you cannot foresee what is going to run. Scheduler Lite is a tool which aims to assist you by allowing you to see what is scheduled to run.
Scheduler Lite is a software tool that has been designed and developed by myself, Colin Greenwood. It is written in Java and compiled using Java 1.6. The product acts as a front end for part of Oracle’s scheduling system as of Oracle 10g. The Lite in the products name, Scheduler Lite,denotes that it is a cut down version of Scheduler FE. The product is free to download and use in any environment you may choose including production.
Scheduler Lite aims to assist the Scheduler Manager in allowing him/her to see which Jobs are going to run and which Jobs have run.
To set up the system create an icon on your desktop that has the following as the target :-
{Directory Name}\SchedulerLite.jar
Download SchedulerLite - SchedulerLite.jar placing it in the target directory.
This is all that is involved in setting up the system.
Upon starting the system the screen display as shown below will be displayed. At the top of the screen is the menu bar.
The individual buttons will be described later. Below the menu bar is the information bar which will show the current user and the current host database. On the screen shown above these two entries are blank as the system has not logged into any database yet. Below the information bar is the main data panel.
To log into a database press the “Connect” button. The result will be that the log in screen will appear as shown below. On entering a valid username/password and host name the screen shown in the Estimated Job Runs Section will be displayed. This shows the jobs that it is estimated will run on the current day. When the Scheduler Lite system is started the date is set at the current date and this remains the case when the user logs into a database.
The final screen is the Logs of Jobs that have run which is displayed in the respective section. This can be displayed by entering the “Logs” button. The user switches between the Estimated runs and the Log runs by using the two buttons entitled “Estimate” and “Logs” respectively.
To the right of these two buttons are the two buttons entitled “Prev.” and “Next”. These refer to the date and the result of pressing the next button is to add one day to the date displayed. The data displayed in the main data area will be refreshed with either the Estimated or Log data for that day depending on which screen is currently selected.
Of the remaining buttons the “Disconn.” Button when pressed results in the system disconnecting from the database and the first introductory screen being redisplayed. The final button is the “Exit” button which when pressed results in the user exiting from the system.
SchedulerLite - Estimated Job Runs Screen.
The Estimated Job Runs Screen displays five columns. These are as follows:-
- Log Date/Time
- Job Owner
- Job Name
- Last Run Duration
- Schedule Type
All of the data that is displayed is obtained from the Job object entry with the exception of the Run Date/Time which is calculated using the Oracle package/procedure Dbms_Scheduler.Evaluate_Calendar_String.
The system works through all the jobs that are currently entered into the scheduling system. For each job it checks that it is enabled and if it is not then the processing fetches the next job.
Otherwise the Schedule Type is checked. There are five possible values. These are as follows:-
- Named
- Calendar
- Once
- Window
- Window_Group
If the Job has a Named schedule then the schedule object is retrieved. The system then calls the Oracle package Dbms_Scheduler.Evaluate_Calendar_String obtaining all of the run dates for the currently displayed date. If the dates fall within the start date and end date given in the scheduler object then the entry is shown.
If the Job has a Calendar schedule then the repeat interval, start date and end date is obtained from the Job itself. The system calls the Oracle package Dbms_Scheduler.Evaluate_Calendar_String obtaing all of the run dates for the currently displayed date. If the dates fall within the start and end date given in the Job object then the entry is displayed.
If the Job is a once only job then the start date is checked against the currently displayed date and if it is valid the entry is displayed.
If the Job has a Window Schedule then the Window object is retrieved. This is checked to see that it is enabled and if this is the case then the schedule type of the window is checked. This can be set to either Named, Calendar or Once. If it is set to once then the Start date of the Window object is checked against the current date and if it is valid then the entry is displayed. If the schedule type of the window is set to Calendar then the Oracle package Dbms_Scheduler.Evaluate_Calendar_String is called obtaining all the entries that can fall within the current date. If these entries fall within the start date and end date of the window then the entries are displayed. If the scheduler type of the window is set to named then the named schedule object is retrieved. The Oracle package Dbms_Scheduler.Evaluate_Calendar_String is then called obtaining all the entries for the current date. If these entries fall within the start date and end date of the schedule object then the entries are displayed.
If the Job has a Window_Group schedule type then the system retrives each of the windows that are assigned to that Window Group and carries out the same processing as it does for a Window schedule type.
This then is the processing that is carried out to display the Estimated Job Run Times.
SchedulerLite - Logs of Job Run Times Screen.
The processing involved in displaying the Logs of the Jobs that have run is much simpler then the Estimated Job Runs. It looks at the entries in the Log entries view and displays the entries that have a log date set to the currently set date.
The following columns are displayed on the screen
- Log Date/Time
- Job Owner
- Job Name
- Last Run Duration
- Status
All of these values are obtained from the Job Logs view.
The Scheduler Lite system is then a program that is simple to operate and that provides the Scheduling Manager with invaluable data that will assist him in managing the Scheduling system. It displays the jobs that are expected to run thereby allowing the Scheduling Manager to identify jobs that he/she is not expecting to be there and to identify jobs that he/she expects to be running but is not. The investigations can then occur prior to the event and not after it thereby proactively finding solutions.
The addition of the logs allows a comparison of the expected and actual job runs to take place. This again can provide the Scheduling Manager with invaluable information.