.NODE

Creating the Quartz Database Structure

JobStores based on JDBC require a database for the Scheduler information to be persisted. Quartz requires 12 database tables to be created. The table names and description are listed in Table 6.1.

Table 6.1. Quartz Requires the Following Tables for All JDBC-persistent JobStores

Table Name

Description

QRTZ_CALENDARS

Stores Quartz calendar information as blobs

QRTZ_CRON_TRIGGERS

Stores cron triggers, including cron expression and time zone information

QRTZ_FIRED_TRIGGERS

Stores status information relating to triggers that have fired and the relevant execution information about the related job.

QRTZ_PAUSED_TRIGGER_GRPS

Stores the trigger groups that have been paused

QRTZ_SCHEDULER_STATE

Stores a few pieces of information about the state of the Scheduler and other Scheduler instances (if used within a cluster)

QRTZ_LOCKS

Stores pessimistic lock information for the application (if pessimistic locking is used)

QRTZ_JOB_DETAILS

Stores detailed information for every configured Job

QRTZ_JOB_LISTENERS

Stores information about configured JobListeners

QRTZ_SIMPLE_TRIGGERS

Stores simple triggers, including repeat count, internal, and number of times triggered

QRTZ_BLOB_TRIGGERS

Triggers stores as blobs (this is used when Quartz users create their own custom trigger typeswith JDBC, JobStore does not have specific knowledge about how to store instances)

QRTZ_TRIGGER_LISTENERS

Stores information about configured triggerListeners

QRTZ_TRIGGERS

Stores information about configured triggers

In Table 6.1, all tables start with the prefix QRTZ_. This is the default, but you can change it by providing an alternate prefix in the quartz.properties file. Changing the prefix is necessary if you use multiple table sets for different Scheduler instances. This would be the case if you need multiple nonclustered schedulers but want to use a single database instance.

Installing the Quartz Database Tables

Quartz includes SQL scripts for all the supported database platforms. You can find the SQL scripts in the /docs/dbTables directory, where is the directory where you unzipped the Quartz distribution.

About 18 different database platform scripts are available. This should cover just about any database that you can come up with. If yours is not included, you can use one of the existing ones and modify it for your database platform.

To install the required database tables, open the .sql file that is specifically designed for your database platform and run the commands using your preferred query tool. With MS SQL Server, for example, you need to run the commands in the file tables_sqlServer.sql using the Query Analyzer tool that comes with the database. With certain databases (including MS SQL Server), you need to create an empty database before running the commands. The SQL commands don't include creating the database. You should also pay careful attention to any notes at the top of the SQL file. Usually, you must follow a few instructions before executing the commands. For example, with the MS SQL Server SQL file, you need to modify this command at the top of the file with the name that you gave the empty database when you created it:

USE [enter_db_name_here]

The SQL files create the necessary table structures and also put some basic constraints and indexes on the tables. Later in this chapter, we talk about how you can improve performance by making some additional changes to the structure.


Scheduling in the Enterprise

Getting Started with Quartz

Hello, Quartz

Scheduling Jobs

Cron Triggers and More

JobStores and Persistence

Implementing Quartz Listeners

Using Quartz Plug-Ins

Using Quartz Remotely

Using Quartz with J2EE

Clustering Quartz

Quartz Cookbook

Quartz and Web Applications

Using Quartz with Workflow

Appendix A. Quartz Configuration Reference





Quartz Job Scheduling Framework(c) Building Open Source Enterprise Applications
Quartz Job Scheduling Framework: Building Open Source Enterprise Applications
ISBN: 0131886703
EAN: 2147483647
Year: N/A
Pages: 148
Similar book on Amazon

Flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net