Availability by day and week - mysql

Question

I'm trying to come up with a database structure to account for products that are available on certain days of week and on certain weeks ( odd / even )
An example:
- product1 is available for selling Mondays in odd weeks
- product2 is available everyday on even weeks
- product3 is available on weekends
I thought of isolating the availability in a second table with the product as fk and each condition on a separate row like so:
fk_prod1 weekday 1
fk_prod1 weekparity 1
fk_prod2 onweekday 1
fk_prod1 weekparity 0
In this form I don't know how I would get the products that are available for today, for the rest of the week and next week.
Any suggestions are welcome :)
Queries are also much appreciated!

Answer 1

This may help out :) Might needed adjusted depending on your circumstances with the program but heres an idea:
Table 1: Products
This could hold ProductID, ProductName
So a row could look like this: 1, product1
Table 2: ProductDayMatrix (ProductDayID,ProductDay)
1,Monday
2,Tuesday
3,Wednesday
4,Thursday
5,Friday
6,Saturday
7,Sunday
Table 3: ProductWeekMatrix (ProductWeekID, ProductWeek)
1 = odd weeks
2 = even weeks
or like
1, Week1
2, Week2
3, Week3
4, Week4
Finally then Table 4:
Product Matrix: (ProductID,ProductDayID,ProductWeekID)
This could hold your products and their corresponding data. So you would insert data into this table with your information and it would look like this.
(1,4,2) = Product 1, On a Thursday, on the even weeks.
Or if things need multiple conditions have 2 different tables that would hold the day information.
Like: ProductAvailablityMatrixDay & ProductAvailabilityMatrixWeek
Then those could hold mulitple values for each so if product 1 was on monday and thursday you could insert: (1,1) & (1,4). Then reading from that table would tell you that product 1 was on day 1 and 4. Same goes with the weeks.

Answer 2

Would it be worth considering an approach similar to the way cron jobs are structured?
Your day of the week will always be 1-7
Your week of the month will always be 1-6
So using LIKE would give 0 possible conflicts where 1 could be matched to 10 for example as you won't ever have 2 digits.
So if your product1 it could be:
day = 1
week = 1,3,5
For product2 it would be:
day = 1,2,3,4,5,6,7
week=2,4,6
For product3 it would be:
day=6,7
week=1,2,3,4,5,6 (September this year spans 6 different weeks)
The your queries would be something like:
Today:
"SELECT * FROM availability WHERE day LIKE '%".date("N")."%' AND week LIKE %".(date("W")-date("W",strtotime("first day of the month")))."%'";
// this is using some PHP to get the week of the days of the week and week of the month.
Tomorrow:
"SELECT * FROM availability WHERE day LIKE '%".date("N",strtotime("tomorrow")."%' AND week LIKE %".(date("W",strtotime("tomorrow"))-date("W",strtotime("first day of the month")))."%'";
// this again is using some PHP to get the week of the days of the week and week of the month - you can achieve the same with just MYSQL but I'm more familiar with PHP to give you an idea.
I'm not saying its perfect but unless your going to do more with these rows I don't think the use of foreign keys is going to help you? Hope that helps?