CakePHP / PHP和MySQL数据库架构的重复事件插件

Question

Introduction

Hello, I have spent a good bit of time researching to find the appropriate solution for recurring events on an upcoming project. I have worked with events and recurring events before and I have never found or developed a solution I have liked. So I am thinking of building a Plugin for CakePHP to handle recurrence.

I have two use cases that I would like to use this plugin/classes for:

1. Recurring Events - Calendar or List View
2. Recurring Payments - Sometimes I don't want to use the gateways recurring payments or I want to do notifications of upcoming payments, etc

I am sure there are many other use cases but those are the two I encounter the most frequently, actually the database schema and basic source code should be similar if not completely reusable between the various use cases, anyways.

So what I need help with is deciding the appropriate database schema to use for recurring events. I have two ideas and I think each have their pros and cons, but need to settle on the best overall approach for flexibility, maintainability & performance.

So in either solution I need to be able to add, edit, delete and list the events. I would like to be able to edit a recurring event with the option to edit or delete all days the event occurs or a specific day(s). I would like to have recurrence rules/options similar google calendar. Options like daily, weekly, monthy, yearly, etc.

First Idea

One table called events to store the recurring events. In this approach I would need to parse the recurrence option and essentially loop and create an individaul event based on the recurrence option. So for example if I want to create an event called "Weekly Meeting" with start date of Jan 1st 2012 and end date of Dec 31st 2012 that occurs every Monday, I would create 52 records in the events table. I think this approach would be harder to manage editing and deleting and would take longer to save the event but listing the data should be simple as just querying a date range. It might be a nightmare if you have to change the recurrence for that event.

CREATE TABLE `events` (                                                               
      `id` int(10) unsigned NOT NULL AUTO_INCREMENT,                                      
      `parent_id` int(10) unsigned NOT NULL,                                              
      `start_date` datetime NOT NULL,                                                     
      `end_date` datetime NOT NULL,                                                       
      `title` varchar(150) CHARACTER SET latin1 NOT NULL,                                 
      `description` text CHARACTER SET latin1,                                            
      `created` datetime NOT NULL,                                                        
      `modified` datetime NOT NULL,                                                       
      PRIMARY KEY (`id`)                                                                  
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8

Second Idea

Have multiple tables to handle the recurrence. This would eliminate the editing and deleting issues and saving should be faster too, but I would think querying the data to get the events would be complex (thinking the mysql queries will be complex) and slower. I should mention that this system is going to be reading far more than it is writing events. But I want a general solution that can be reused. I can also use caching to improve reading so it is not a huge concern. Using the example from above instead of 52 entries we would have only one in the events table.

Not sure about the exact schema any ideas?

Thanks in advance for your help and ideas! Want to get a sense of how others handle recurring events.

Answer 1

CREATE TABLE `events` (
    `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
    `parent_id` int(10) unsigned NOT NULL,
    `title` varchar(150) CHARACTER SET latin1 NOT NULL,
    `description` text CHARACTER SET latin1,
    /** Some fields about how the recurring is applied  **/
   `created` datetime NOT NULL,
   `modified` datetime NOT NULL,
   PRIMARY KEY (`id`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8

CREATE TABLE `event_occurrences` (
    `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
    `event_id` int(10) unsigned NOT NULL,
    `date` DATE NOT NULL,
   PRIMARY KEY (`id`)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8

If the recurring details, start or end fields aren't changed there is no need to mess with the event_occurrences. When modifying any of those details DELETE FROM event_occurrences WHERE event_id=? and then have a method that will generate the event_occurrences for a given event id. The same method could be used for creating and modifying.