I want to create a php calender application. What is the optimal database design for this software if I want to create normal, weekly, monthly and yearly events.
I would just create an entry for each recurrence of the event, out to some horizon. However, it means that you'll need another table that you can use to project out the dates if they scan past your horizon date. I.e., you'll need an events table that contains one record for each occurrence of a repeated event (Jan 1, Jan 8, Jan 15, ... through December), and a table with each record available to seed future years (start date: Jan 1; repeat: 7; through: 2011) so that at the start of 2012 (or as soon as the user requests a view of a 2012+ month) you can generate the future events.
This has two big disadvantages:
Your database has data for a full year. However, if adding a full year's worth of data ruins your performance, your system is probably underpowered. (It seems a requirement that a calendar app be able to handle many years' worth of dates)
At the end of the event horizon, you need to generate the future dates for recurring events.
The advantages (IMO) that outweigh the disadvantages:
Easier math when displaying the calendar. Using Tim's method, above, if the user loads Dec 18, 2011, how are you going to calculate which recurring events should be placed on that day? You'll be forced to loop through EVERY recurring event every time you display a date. The tradeoff is disadvantage #1, which I think is the better solution that having to redo these calculations.
You can edit specific instances of an event. Using Tim's method, if a meeting occurred on a holiday and the user changed it to the previous day, how would you even do it? Using the one-entry-per-event method described here, you could just modify that record for the event, easily moving single occurrences around in the calendar.
You could have a column in the EVENT table for RECURRENCE_STATUS which tracks 4 values, does not recur, weekly, monthly, yearly. The query of the day's events would be a union of those that are set to occur on that day and which do not recur with the set of those that do recur and whose initial date's difference from today is a modulo 0 for week, month, and a year differences. The date-math calculations are a little more nuanced than that (because of the varying number of days in the month) but the structure should suffice.
Related
I am creating a system that requires a schedular for a particular task. Users may pick from times 24 hours a day, 7 days a week.
I came up with a few options for the database storage, but I don't think either one is the most efficient design, so I'm hoping for some possible alternatives that may be more efficient.
On the user side I created a grid of buttons with 2 loops to create the days, and the times, and I set each a unique value of $timeValue = "d".$j."-t".$i;
So d1-t0 will be Saturday at Midnight d3-t12= Tuesday at Noon, and so forth.
So, in the database I was first going to simply have a ID, day, time set up, but that would result in a possible 168 rows per event
Then I tried an ID, day, and time 0-23 (a column for each hour of the day) And I was simply going to have a boolean set up. 0 if not selected, 1 if it is.
This would result in 7 rows per event, but I think querying that data might be a pain.
I need to perform a few functions on this data. On each day, list the number of selected times into an array. But I don't believe having a select statement of SELECT * from schedule where time0, =1 or time1= 1 .... ect will work, nor will it produce the desired array. (times=(0,3,5,6,7...)
So, this isnt going to work well.
My overall system will need to also know every event that has each time selected for a mass posting.
"Select * from table where time = $time (0-23) and day= $day (1-7)
Do action with data...
So with this requirement, I'm going to assume that storing the times as an array within the database is likely not the most efficient way either.
So am I stuck with needing up to 168 rows of data per event, or is there a better way I am missing? Thanks
Update:
To give a little more clarity on what I need to accomplish:
Users will be creating event campaigns in which other users can bid on various time slots for something to happen. There will likely be 10-100 thousand of these campaigns at any one time and they are ongoing until the creator stops them. The campaign creators can define the time slots available for their campaign.
At the designated time each day the system will find every campaign that has an event scheduled and perform the event.
So the first requirement is to know which time slots are available for the campaign, and then I need the system to quickly identify campaigns that have an event on each hour and day and perform it automatically.
I'm trying to create a schedule of unique, recurring events that cycle on a weekly basis (each event will have unique identifiers and repeat weekly).
In addition to other information gathered about each event, I will gather the weekday on which each event will take place and the dates (calendar dates) on which the event will begin and end.
An example:
Event: Go to gym (the event I plan to do once a week)
Day of Week: Sunday (day of week event will occur (every Sunday))
Start Date: 2014-09-01 (happens to be a Monday)
End Date: 2015-08-31 (...)
The purpose is to write a script that takes any multitude of events and their respective weekday/start/end date and recreate a calendar depicting the future calendar dates on which each event will occur.
So the first date I should see scheduled to go to the gym will be:
2014-09-07
because this is first Sunday following the start date.
To sum it up, I am gathering the weekday of each event as well as the start and end dates. How can I parse these pieces of data into something that spits out a list of the events' future dates of reoccurrence?
Keep in mind that there will be a vast number of events that will occur on different days of the week and have different start/end dates.
Thank you for all who read and respond.
Tried:
SQL: grouping, different select statements, and stuff
PHP: stuff, date/time stuff, and stuff stuff
For next event in schedule you could use strtotime function:
strtotime('2014-09-01 next Sunday');
and use returned UNIX time.
But for complete solution of your problem there can be many ways. IMHO, strtotime used in for cycle can give you a large overhead if calculated on demand. If you store schedule in DB, perhaps it will be easiest solution to generete dates and regenerate them on edit.
In other hand, dates are pain in head so algoritm to calculate all ocasions can be much bigger. You can use intervals calculated from difference of result date from first date if $firstDate = $startDate or if event happens every day once a week, then just add 7 days to it.
Post more details or your solution to find mistakes.
I am building a Time Clock application with PHP and Laravel 4.
My boss requires that he is able to pull and build different reports based on the data I store in the database for a Time Card record.
Right now I store a DateTime for clock in and clock out as well as a Timestamp for both those times as well into the Database.
I need to be able to Query the database and build reports for different Pay Periods for a user.
So for example I will store in another Database Table, records that will be for a User ID and will have different Pay Periods. So a Start day may be the 1st of the month and end date the 15th and that is 1 pay period (roughly 2 weeks) I am not sure the best way to store these records really.
Another will be the 16th of the month to the end of the month. So the end date would be different depending on how many days are in a month
I am not sure about the best way to define these Pay periods for a user. I can't simply say 1-15 and then 16-30 since the 30 would be a different number for each month.
Would appreciate any insight into how this could be done?
So I can build reports for any Pay Periods since not every user gets paid every 2 weeks it needs to be flexible so that I can define it on a per user basis
This question is more about the Logic instead of actual code.
Welcome to the wonderful world of Time and Attendance. You are touching the tip of the iceberg. You may find that purchasing a pre-packaged product may be easier than writing your own.
That said, I can offer you the following general advice:
Be very careful of your data types and how they are used, both in PHP and in MySQL.
You need to make sure you understand local time vs UTC, time zones, and daylight saving time. In general, you don't want to store local time unless you also store its offset from UTC. Otherwise you will have ambiguity around daylight saving time changes. This is important even if you only have one time zone to deal with.
When it comes to Pay Periods, the common types are:
Weekly
Bi-Weekly
Semi-Monthly
Monthly
Every X days starting from Y
In some systems, each individual pay period can be adjusted +/- a number of days from it's normal date. When doing so, the bordering period must also be adjusted to compensate.
You should start with business logic that can calculate the start and end date for a pay period given any particular date and time. You can then expand that to easily get the prior or next pay period.
You can store each pay period into it's own table, but it's not necessarily required. That will depend on a lot of specifics about your system internals.
Because a pay period is defined by dates, you have the "Whose Day is it?" problem. It might be the day as defined by the company, or if employees are in different time zones, then it might be the "logical day". If you only have one time zone to deal with then, you are lucky in this regard.
When comparing against the pay period, use half-open intervals, [start, end). In other words:
periodStart <= punchTime < periodEnd
or likewise
periodStart <= punchTime && periodEnd > punchTime
The end of one period should be exactly the same as the start of the next. Don't try to define the end of the period at some silly value like 23:59:59.999...
As you can see, this is just the beginning. I hope this is useful to you. If you can narrow the focus of your question further, I'll be happy to help more. Otherwise, it's like asking for how to build an ERP system when you're not sure what structure to store inventory.
I think you are over thinking this. Let thte user define the start and end dates.
You will need the UserId, a timestamp (time in and time out) of the user and that should be about it.
I picture something like this:
UserId | DateIn | DateOut
On the page you could put put dropdowns (or if you want a nifty interface a datepicker that uses javascript) and allow the manager to pick a start and end date that he wants to choose.
So if he wants to see an employees time between Jan. 1 and Feb. 31 he can choose those as his start and end dates.
This will allow things to be very flexible, for example the manager can choose Feb 16 as start date and Feb 29 as end date. It makes sense to allow him to choose the data requirements so he can view whatever he wants.
EDIT:
An example from my comment below this post you could do something like:
$startDate = new DateTime();
$startDate->modify('first day of this month'); //or 16th for second part of bi-monthly
$startDate->format(#some date formatting as you need#);
$endDate = new DateTime();
$endDate->modify('last day of this month'); //or 15th for first part of bi-monthly
$endDate->format(#some date formatting as you need#);
If things are even less defined however you could always try doing special math. date('t') will give you the number of days in a month. I would refrain from using this unless your pay days are fixed such as paid every 6 days.
In general I would harness the power of the PHP DateTime class over using date() function. http://php.net/manual/en/class.datetime.php
I have search over php mysql recurring events but didnt find anything exactly like i want.
I want to develop event sheduler in php mysql in which user add reccuring events based on daily,weekly,montly,yearly patterns using html form which is stored in mysql using php.
Like for example
user will enter start date,end date, what time event will happen(like 4:30pm) and duration of the event(like 2 hrs so it will make 430pm to 630pm event) with repeating patterns.For example event will repeat after 3 days , on monday and wednesday every week or after every two weeks, every 10th day of month or every 10th day after two months, on specific date every year or without any repeating patterns just add event for any specific date .
This information will be taken from user using html form and will be stored in mysql database and than it needs to display user upcoming events(e.g consider today is 13th july 2013 if recurring event is sheduled for 15th july 2013 it will consider as upcoming events) or events in the past(e.g consider today is 13th july 2013 if event is sheduled for 10th july 2013 it will be consider as past event) using php in two different ways using html table and arshaw full calendar.
I need help how i store event information in mysql database and than pull it using php and display upcoming or past events in html table and also be to integrate it arshaw full calendar.
This sort of stuff is already working in musicteacherhelper.com which also used php and mysql for implementing so i need to know is there any open source code available to implement this functionality.
Any help in this regard will be highly appreciated.
Thanks
Talha
use industry standard RRULE to store the informaton and some metadata of event in some mysql table for search purpose (example : date range)
http://www.kanzaki.com/docs/ical/rrule.html
demo : http://jkbr.github.io/rrule/
there are js and php libraries available for the same.
I want to create a a calendar like google calendar to keep track of people's upcoming events.
The problem is that people can have recurring events. Events that occur every week or every 2 days or every 1 month etc or every 4 weeks
But I want to be able to list upcoming events...
How do I do that using php and mysql?
For example if an event that occurs once every week from 10/31 to 11/30, do I have to create a separate row in the database for each week?
But what if the event occurs every weekday from 10/31 until forever?
I just want people to add events into the database, and then list upcoming events that they have coming up.
I also want to have a cron job that reminds people of upcoming events.
If I have a cron job - if I store each event once (for example an event that occurs once every 2 days, I store it as one row in the database describing that it occurs once every two days), then I would have to do a lot of calculations each time I run the cron job to figure out whether the event occurs today (considering it is is supposed to occur once every 2 days, I need to calculate if today is one of those days that it occurs).
Is there an easier way to approach this?
I let people set the following recurring properties:
event occurs every X number days, X number weeks, X number months,
event occurs every weekday from DATE to DATE, or from DATE to forever
event occurs every month, week, every Mon Wed Fri, or every Tues Thurs