About Oracle's scheduler and job

Oracle Scheduler is a job for managing and scheduling databases, allowing many regular database tasks to be automated, reducing human intervention, freeing labor, and essentially, it's crontab with Linux, business Mission management software like Autosys, UC4, Just as their domain is different, Oracle Scheduler is focused on automating management, maintenance, and monitoring of Oracle database jobs.

This article is a theoretical article, introduced the basic concept of Oracle Scheduler, Oracle Scheduler Many nouns, described below:

Program (Procedure)

Program is the object that the job executes, such as stored procedures, pl/sql blocks, external executable programs, etc.

Schedule (PLAN)

Schedule defines when a job executes, and how many times it executes, with the following two similar schedule:

1 Based on time schedule (Schedule)

2 event-based Plan (event Schedule)

Destination (place)

The destination defines where job execution is performed, with the following two types:

1 Database destination: Indicates that the job executes in the database (contains both local and remote databases)

2) external (External destination): Indicates that the job executes outside the database

It is important to note that if the job is performed remotely, the scheduler agent must be installed on the remote host.

File Watcher (document keeper)

The file keeper defines the destination, file name, and so on, triggering an event once a qualifying file arrives, starting the job

Credential (Certified)

Credential defines the user password pair, only through the certification job to start, there are mainly the following two kinds of authentication:

1) Remote database authentication

2 external certification (such as operating system)

Chain (Task chain)

Chain used to define a series of job execution dependencies

Window (Time window)

The time window defines the resource allocation for a job within a time period of the day.

Group (groups)

A series of identical objects consists of group, which has the following three types of group:

1) Database Destination Group

2) External Destination Group

3) Window Group

How does Job, program, and schedule interact?

The diagram above shows the relationship between them, the same program can be called by multiple jobs, and similarly, multiple jobs can share the same Schedule