Resource scheduling logic - sql

I've to schedule few resource for booking. Below is my logic
Sample:
I've to schedule Delux(2) and Classic(1) room for a year. So I'm inserting 1095 records(730+365-a row for every day each resource).
Database:
table(SID,SDATE,ROOMID,STATUS)
For the particular day, I'm checking the schedule count which has status as 'available' and allowing to book.
Is the logic correct one? or any other logic which reduce number of record insertion?(Note:resource count per day may vary)

Why can't you use START_DATE and END_DATE instead of the SDATE to store intervals?
For the particular day you can ask the same status for intervals where the day between the interval's START_DATE and END_DATE.
Even better to track only booked intervals all the rest are free. So all rooms are free except defined intervals for already booked ones.

If I understand the problem correctly you have a variable resource pool that you receive somehow. Assuming this is in the form of room X of type T from date A to date B.
I would store this into a table "availability", so at any time you can have a view on overall availability per day. If you couple this with StanislavL answer you would have two tables one for available rooms and one for bookings:
availability(availability_id,room_id,date_from,date_to)
booking(booking_id,room_id,date_from,date_to)
room(room_id,type,name,address,..)
Number of available rooms per day is obtained by subtracting via NOT IN clause the booked rooms from the available ones. Also, when you need to book a room you can check in the availability table if this is actually possible.

Related

vb.net calculating booked appointment times from a list of available times?

I'm trying to find an efficient way to calculate the booked times for a user(object), given a list of free/available times for the same user\object.
I have an object that will return the "available" times for a given specific day. The duration/end time is fixed to 10 minutes.
Example Starting data:
12/23/2020 8:00 AM
12/23/2020 9:00 AM
12/23/2020 1:00 PM
In this case I need to generate the "unavailable" times and insert them into a database with a fairly simple schema:
start_date | end_date | start_time | end_time
The inserting is fairly trivial, i'm having a hard time determining the best way to calculate the unavailable timespans.
Using the example above i would need to generate the following timespans:
12/23/2020 12:00 AM - 7:59 AM
12/23/2020 08:11 AM - 8:59 AM
12/23/2020 09:11 AM - 12:59 PM
12/23/2020 1:11 PM - 11:59 PM
Any frameworks or libraries that can do the heavy lifting on this for me? Is it possible to solve this problem without looping through the results and calculating all of the offsets?
To anyone asking "why" - hooking together two legacy systems, one system returns the available appointments for a given date this needs to be plumbed into a system that needs the un-available appointments for a given date.
Well, first I written more tour booking systems then I can shake a stick at.
The one Rosetta stone that holds true?
You don't want to generate or have booking slots that are NOT being used in the system PERIOD!!!
Thus you ONLY ever enter into the system a valid booking (starttime, and end time). And that startTime should be a datetime column - this will VAST reduce the complexity of your queries. Given you have date and separate time? Well, then your queries will be more complex - I'll leave that to you.
Given the above? The simple logic to find a booking collision in ALL cases is this:
A collision occurs when:
RequestStartDate <= EndDate
and
RequestEndDate >= StartDate
Now in above, I assume date values, or datetime values.
So if I want a list of any booking for today?
RequestDDTStart = 2020-12-23 9 AM
RequestDTEnd = 2020-12-23 5 PM
And thus any collision can be found with this:
strWhere= dtRequestStartDate <= BookingEndDate" & _
" and dtRequestEndDate >= BookingStartDate"
Now, assumging .net, then above would be something like this as parameters
strWhere= #dtRequestStart <= BookingEndDate" & _
" and #dtRequestEnd >= BookingStartDate"
So, above would return all bookings for today 9 am to 5 pm
A REMARKABLE simple query! Now of course the above query could/would include the exam room, or hotel room or whatever as an additional criteria. But in ALL cases the above simple query returns ANY collision for that 9 am to 5 pm.
And the beauty of this system? As long as you never allow a over-lap into the booking system, then you can book a 10 minute or a 20 minute or a 30 minute session as ONE entry into the database. I would thus not need to create 3x 10 minute slots.
So, this means you NEVER have to create booking slots. The whole system will and can be driver with a simple start + end booking record. And as noted, then you can book 1 hour, or 40 minutes. Your input (UI) can simple limit the time span to increments of 10 minutes - but that's the UI part.
Now I suppose to display things in 10 minute increments on a screen? Well, then you would have to submit 6 requests per hour to "display" the time slots. For a whole day, that suggest for 9 am to 5 pm, you would have to run 8 x 6 = 48 requests to get a list of 10 minute increments. But then again, you COULD just show the existing bookings for a day, and allow new bookings to be added - but don't allow if there is a over lap.
So, as noted, the concept here is you don't really need "slots" in the database. I suppose you could try slots, but it makes the code a HUGE mess to deal with. if you ONLY ever store the start + end? Then I can say move the booking to another day by JUST changing the date. Or I can extend a booking from 10 minutes to say 20 or 40 minutes - and ONLY have to change the end time. As long as no overlap occurs with the above simple "test", then I can simple change the booking to be 40 minutes in length - and ZERO code to update multiple slots is required. And same goes for reducing a booking from 40 minutes to 10 minutes. Again ONLY the end time need be reduced - a ONE row update into the database.
So if at all possible, I would dump the concept of having "slots" in the database. I might consider such a design if a booking was only ever 10 minutes. But if 10 or 20 or 30 is allowed, then you don't need to store ANY un-used slots in the database, but ONLY ever store a valid booked slot. Empty un-used time can thus ALSO be found with the above query. (if the query returns records - then you can't book).
So display of free time in some UI becomes more of a challenge, but showing bookings that span 10 or 20 or whatever minutes is far more easy, and as noted, you can even change a whole booking to a different room by a ONE row update of the room ID. If no collision occurs, then you allow this booking - and you achieve this result by ONLY updating one simple booking record that represents that start + end time.
and this means you also NEVER store the booking totals in the database - you query them!
I also found that if I say store any booking totals in the database? Well, with complex code, we always found that the totals often don't match perfect. So then we wind up writing a routine to go though the data, sum up the totals and write those out.
But, if you never store any booked totals (say people on a bus, or people in a given hotel), then while the query for such display is somewhat more difficult, it becomes dead simple to remove a person from say a tour by simple null out of the tourID.
So, this display shows the above concepts in Action. And the available rooms in the hotel, people booked on bus, and even totals for "group tours" are ALL values NOT stored in the database:
So in above, people booked on bus, booked in rooms, and rooms used? All those values are NOT stored in the database. And no slots exist either. So if we have a bus, then we set the capacity of 46, but we do NOT create 46 slots to book into. So be it a bus, a hotel, a medical exam room? You don't create booking slots ahead of time, but simply insert bookings with a start + end, and then query against that concept.
So, to find a total on a bus (or say in a exam room), I query to find the total for that day. And if I want to move a group booking of 4 people from one bus to another? Then one FK update to the given bus they are on allows the whole system to "cascade" the existing values in the system. And same goes for moving a person from exam room #1 to #5. You only have to update the FK value of the exam room. If no collisions occur, then this again is a one row update. If you have multiple exam rooms, and multiple slots, then what should be a simple one row update in the database becomes a whole hodge podge of now having to update multiple booking slots with whacks of code.
So you book "use" of resources "into" a "day" a "bus" a room, but it is the act of that booking that consumes the time slots - not that you pre-create records or timeslots for each "range". This thus allows you to leverage the relatonal database model, and reduce huge amounts of code - since you not coding against "slots", but only that a exam room is open from 10 am to 4 pm. That available room for that day is thus ONLY ONE record you create in the system, and then you are now free to book into that one day given room range. The bookings into that one room for the day can be 10 minutes, or 40 minutes - but it ONLY one record being added into the database to achieve this goal (booking).
Regardless of the above, that simple collision query works for any collision (including a whole overlap, inside a existing span, or even the end or start overlaps any booking. And that query is dead simple - and it works for all collisions. So I don't have a library to share, but that simple booking collision finder query can thus drive the whole system based on that kind of simple query.

How to store availability information in SQL, including recurring items

So I'm developing a database for an agency that manages many relief staff.
Relief workers set their availability for each day in one of three categories (day, evening, night).
We also need to be able to set some part-time relief workers as busy on weekly, biweekly, and in one instance, on a 9-week rotation. Since we're already developing recurring patterns of availability here, we might as well also give the relief workers the option of setting recurring availability days.
We also need to be able to query the database, and determine if an employee is available for a given day.
But here's the gotcha - we need to be able to use change data capture. So I'm not sure if calculating availability is the best option.
My SQL prototype table looks like this:
TABLE Availability Day
employee_id_fk | workday (DATETIME) | day | eve | night (all booleans)| worksite_code_fk (can be null)
I'm really struggling how to wrap my head around recurring events. I could create say, a years worth, of availability days following a pattern in 'x' day cycle. But how far ahead of time do we store information? I can see running into problems when we reach the end of the data set.
I was thinking of storing say, 6 months of information, then adding a server side task that runs monthly to keep the tables updated with 6 months of data, but my intuition is telling me this is a bad fix.
For absolutely flexibility in the future and keeping data from bloating my first thought would be something like
Calendar Dimension Table - Make it for like 100 years or Whatever you Want make it include day of week information etc.
Time Dimension Table - Hour, Minutes, every 15 what ever but only for 24 hour period
Shifts Table - 1 record per shift e.g. Day, Evening, and Night
Specific Availability Table - Relationship to Calendar & Time with Start & Stops recommend 1 record per day so even if they choose a range of 7 days split that to 1 record perday and 1 record per shift.
Recurring Availability Table - for day of week (1-7),Month,WeekOfYear, whatever you can think of. But again I am thinking 1 record per value so if they are available Mondays and Tuesday's that would be 2 rows. and if multiple shifts then it would be multiple rows.
Now and here is the perhaps the weird part, I would put a Available Column on the Specific and Recurring Availability Tables, maybe make it a tiny int and store something like 0 not available, 1 available, 2 maybe available, 3 available with notice.
If you want to take into account Availability with Notice you could add columns for that too such as x # of days. If you want full flexibility maybe that becomes a related table too.
The queries would be complex but you could use a stored procedure or a table valued function to handle it fairly routinely.

Table design for payments

I have a table that holds data for a person who is on a project. The table has a Start date field a nullable End date field. So, a person is on a project from Start to End.
At the moment, they are always billable to the project. But I now have a new requirement that, for a period, they can be non-billable, yet, still working on the project. So, they have been assigned to the project, and are working, but for some reason, the client isn't billed for part of the period they are assigned, or maybe billed at a lower rate.
My idea is to have an exclusion type table, linked to the person assignment table which would have a start date, and end date, and a Rate column, which could be set to zero for no-charge, or else, works as an override value for a period.
Does this seem like valid design? As the person is billed 95% of the time, and probably will never had any exclusion, it makes more sense to me to have an exclusion table.
If anyone has an idea of how to do this better, it would be great.
At the moment, I also have a 'calendar' table, which I join to based on the start/end date of the person's schedule to get the daily rate. So, I could then join to the exclusion date as well, to see if there is an override of the rate?
Issues I might find with my design, are a lot of the joins are based on:
ON DateValue BETWEEN Start AND End
And I am not sure they're the most efficient joins.
If the exception could be one or more period of times (one-to-many) for one project then your design using an exclusion table is the best design.
Example:
June 1, 2013 to June 30, 2013
Exclusion:
June 9, 2013 - 0 Rate
June 25 to 27 - 30% of Original Rate
However, if the exclusion is possible and can only be a maximum of ONE single period (or one-to-one type of relationship) then you might instead put it on the same fields as other fields on project table.
Example:
June 1, 2013 to June 30, 2013
Exclusion:
June 9, 2013 - 0 Rate
I would use this "exclusion" table as single storage for person-project occupation data. In case when person is assigned to project one time without changes in rate, you will have one record in this table. In other cases you will have a history of rate changes in this table.
It looks like your are allowing discount on standard rate to the customer for specific period. for such case, you can set the rate to be negative eg.-$100/hours for the duration to set resource rate for free in your discount/exclusion table. you can find the final rate for that resource for particular period by adding your discount amount and standard amount to get net amount. In your design, you have already mentioned the relation will be made between exclusion and person assignment table. your design will allow to show what discount has been given to the customer. This approach is ok when your are adjusting the billing for exception cases.
In case, your are trying to do correction in project billing, IMO, you should have separate entries in person assignment table for each rate with the duration.
While generating Invoice to the customer, you can show adjusted discounted rate or new revised billing based on the correction.

how to model (mvc) an abstract time period for employe shift management

I've started thinking about an employee shift management application to handle the shifts (who works when, trading, etc) at my current workplace (that uses pen and paper and hasn't got anyway for us employees to communicate about changes without going through the boss and be on site).
Currently the shifts are modeled loosely as:
There is a recurring 4 week period (from Monday week 1 to Sunday week 4)
There is a template for placing employees in this 4 week period
Every 4 months (ie 3 times a year) the 4 week template is projected over the next 4 month period
The shifts have been the same for a long time and it seems many employees would prefer to have them changed (I can say this by the requests for change that come in every time a new 4 month is set).
What I'm aiming at are the models:
Shift_group_tpl (the 4 week period above)
Shift_tpl (a single shift in the 4 week period, including info on who defaults to work this shift)
Shift_group (a set period of time whit actual shifts)
Shift (a set shift whit a real time period and an employee - and the possibility to be changed both in start_time, end_time and employee)
I've thought of a way to do this with recurring iCalendar events: Creating RRULE's (without an endtime) and then calculate (using temporary start and end times) if that specific Shift_group_tpl could be used within a real Shift_group. (The problem with this approach is that I can't figure out how to trim the Shift_group_tpl's to fit into the start or end of a Shift_group.)
What I'm looking for are some other perspectives or ways of doing it or even just a pat on the shoulder letting me know that I'm on the right track (and then giving advice on the trimming problem).
/iole1
What I'm aiming at are the models:
Shift_group_tpl (the 4 week period above)
Shift_tpl (a single shift in the 4 week period, including info on who defaults to work this shift)
Shift_group (a set period of time whit actual shifts)
Shift (a set shift whit a real time period and an employee - and the possibility to be changed both in start_time, end_time and employee)
You have "sql" as a tag for this post? So im guessing you want these as SQL tables?
By the sounds, the problem is that your considering the data you have, rather than the abstract concepts you need to store that data. Which is what you'd need to do to create an application. (Most likely a "Shifts" table, rather than the four tables above).
There is little information here to help, Consider refining your thoughts and ask another question.

Recurring Orders

Hi everyone I'm working on a school project, and for my project I chose to create an ecommerce system that can process recurring orders. This is for my final project, I'll be graduating in May with an associates in computer science.
Keep in mind this is no where a final solution and it's basically a jumping off point for this database design.
A little background on the business processes.
- Customer will order a product, and will specify during checkout whether it is a one time order or a weekly/monthly order.
- Customer will specify a location in which to pick up their order (this location is specific only to the order)
- If the value of the order > 25.00 then it is accepted otherwise it is rejected.
- This will populate the orders_test and order_products_test tables respectively
Person on the back end will have a report generated for deliveries for the day based on these two tables.
They will be able to print it off and it will generate a list of what items go to what location.
Based on the following criteria.
date_of_next_scheduled_delivery = current date
remaining_deliveries > 0
Once they are satisfied with the delivery list they will press "Process Deliveries" button.
This will adjust the order_products_test table as follows
Subtract 1 from remaining_deliveries
Insert current date into date_of_last_delivery_processed
Based on delivery_frequency (i.e. once, weekly, monthly) it will change the date_of_next_scheduled_delivery
status values in the order_products_test table can either be active, hold, or canceled, expired
I just would like some opinions if I am approaching this correctly or if I should scratch this approach and start over again.
A few thoughts, though not necessarily complete (there's a lot to your question, but hopefully these points help):
I don't think you need to keep track of remaining deliveries. You only have 2 options - a one time order, or a recurring order. In both cases, there's no sense in calculating remaining deliveries. It's never leveraged.
In terms of tracking the next delivery date, you can just keep track of the day of the order. If it's recurring -- monthly or weekly, regardless -- everything is calculable from that first date. Most DB systems (MySQL, SQL Server, Oracle, etc) support more than enough date computation flexibility so that you can calculate this on the fly, as opposed to maintaining such a known schedule.
If the delivery location is only specific to the order, I see no use in creating a separate table for it -- it's functionally dependent on the order, you should keep it in the same table as the order. For most e-commerce systems, this is not the case because they tend to associate a list of delivery locations with accounts, which they prompt you about when you order more than once (e.g., Amazon).
Given the above, I bet you can just get away with 2 of your 4 tables above -- Account and Order. But again, if delivery locations are associated with Accounts, I would indeed break that out. (but your question above doesn't suggest that)
Do not name your tables with a "_test" suffix -- it's confusing.