Tables in the Object File System are versioned, and rows are stored in objects. Insert, update, and delete operations create new versions of the table. When a row is deleted from the table rather than deleting the row from the object, a new object is created without the row. The latest version of the table is the current version. Previous versions of the table are retained for a retention period. The default retention period is 30 days. When a previous version is older than the retention period, the version is obsolete. Obsolete versions are removed by a stored procedure in the database TD_OFSDB. The user TD_OFS has the privilege to run the purge stored procedure.
Users, with the appropriate permissions, can use Object File System (OFS) Scheduler to purge their older tables, and to cancel their purge jobs. Administrators use OFS Scheduler to schedule when to run the purge jobs on all older tables, to cancel all current purge requests, to start the scheduler, and to stop the scheduler from accepting new jobs.
- AlterJob: Set schedule for a job.
- AbortJob: Cancel a running job. Subsequent scheduled jobs are not affected.
- AlterJobAdmin: Set job schedules.
- AbortJobAdmin: Cancel all running jobs. Subsequent scheduled jobs are not affected.
- StartScheduler: Start the OFS Scheduler. Jobs start at their next scheduled time.
- StopScheduler: Stop the OFS Scheduler from submitting new jobs. Any running requests are allowed to complete.
ScheduleString Syntax
ScheduleString supports up to 32 sessions.
{ RUN
{ ONCE
| REPEAT <repeat_string>
| AFTER <before_job_name> [{ SUCCEEDS | FAIL }]
}
}
<repeat_string> = <day_string><hour_string> [<day_string><hour_string>…] <day_string> = DAYS = day_num[,… | - day_num];] <hour_string> = HOURS = hour_num[,… | - hour_num];]
Scheduled Jobs
OFS Scheduler is started automatically. The following jobs are scheduled to run.
| UserName | JobName | RunEnabled | ScheduleString |
|---|---|---|---|
| TD_ScheduleINT | MoveHistory | T | REPEAT DAYS=1-7; HOURS=0 |
| TD_OFS | MoveOFSLog | T | REPEAT DAYS=1-7; HOURS=0 |
| TD_OFS | MoveReorgLog | T | REPEAT DAYS=1-7; HOURS=0 |
| TD_OFS | PurgeAllOldVersions | T | REPEAT DAYS=1-7; HOURS=0-23 |
| TD_OFS | ReorganizeTablesPrep | T | REPEAT DAYS=1-7; HOURS=0-23 |
| TD_OFS | ReorganizeTables | T | RUN AFTER REORGANIZETABLESPREP |
The following query and result show the check for jobs at the next runtime.
Querysel JobId, JobName (char(30)), NextRuntime from TD_ScheduleDB.JobTbl order by 1;Result
JobId JobName NextRuntime
----------- ------------------------------ --------------------------------
8 PurgeAllOldVersions 2025-01-10 00:00:00.000000-00:00
9 MoveHistory 2025-01-10 00:00:00.000000-00:00
10 MoveOFSLog 2025-01-10 00:00:00.000000-00:00
11 MoveReorgLog 2025-01-10 00:00:00.000000-00:00
12 ReorganizeTablesPrep 2025-01-10 00:00:00.000000-00:00
13 ReorganizeTables ?
Database and Users for OFS Scheduler
- SELECT
- CREATE TABLE
- CREATE PROCEDURE
- INSERT
- UPDATE
- DELETE
The scheduler has users TD_Schedule and TD_ScheduleINT that have permissions on the TD_ScheduleDB database. TD_Schedule is for users, and TD_ScheduleINT is used by the scheduler to maintain the tables in TD_ScheduleDB.
Reorganization of OFS Tables
While the OFS scheduler handles table organization and purging, administrators can use scheduler jobs and procedures to exclude tables and databases from this process. See Reorganizing OFS Tables using OFS Scheduler.