I am creating an attendance system and i want to automatically change the subject based on the time of the day. I have a table consist of subject name, start time, end time and its day. I have a question, is it possible to automatically get the value of a row based on specific time and day?
For example the current time is 12:45 PM and the day is Tuesday. This is my sample table. Then the output will be Principles of OS.
in mysql to get the name the current day use
DAYNAME(date)
and compare it to your sub_day column in selection
Related
Developers, I am working on a report that I have to display the companies ranking based on some conditions for the date range which comes from front. Ex: last week, I have done that, but now I want to show how many weeks that a particular company be in same rank. If I am checking the past week I have to check the ranking for each week from the year start. If last week first position company and other weeks first position company is same I have make the count as increasing accordingly. When I querying the data for each week using the for loop it is taking around 42s to process and display the data. Also I tried to fetch whole data from first week of the year to current week then I filtered the array but this also takes long time. Can anyone give any other ideas to overcome this? Thanks in advance.
As far as I understand your problem - then storage of aggregated data should help you.
Create a table in the database, let's say "archive_rating", with 3 fields: week_number (let from January 1, 2000), company_id, company_position in your rating. Don't forget the index for the week_number field.
At 00:00:00 every Monday, run a background task that will save the positions for each company to an archive table.
This will allow you not to calculate a rating for each week from the beginning of the year. You will already have it.
I have a table in Access that lists all classes at a school. I'm trying to create a field that indicates what day of week class meets (Monday, Tuesday, etc), and another field for what time of day the class starts (2:30 pm etc.). I shouldn't have to input an actual calendar date, because these values stand for a schedule that occurs weekly. It seems my only option is to use a text field? Surely this has been solved a thousand times. What would be best practice for this type of application?
Use some arbitrary date this has the first weekday of your weeks.
Add one day for every subsequent weekday, and apply the format dddd to display the weekday name.
Apply a time part as needed, and set the format when displaying the values to Short Time or similar.
I am stuck with a problem. In an app's db, I am having a schedule table which will store user provided schedules. E.g
Daily
Every Week
Twice a Week
Every 3rd (or any user chosen) day of week
Every Month
Twice a month
Every x day of month
Every x month of year
And so on. These schedules will then provide reference point to schedule different tasks or identify their repeat-ance.
I am not able to think of a proper database structure for it. The best I can get is to have a table with following columns:
Day
Week
Month
Year
type
Then store the specified schedule in the related column and provide the type.
e.g Every week can go like 1 in week column and 1 (designated value for repeating whole) or something like that.
The problem with this approach is that this table is gonna be used very frequently and the data retrieved will not be straightforward. It will need calculation to know the schedule type and hence will require complex db queries to get each type of schedule.
I am implementing it in Laravel app if that can provide any other methodology. It's a SAAS app with huge amount of data related to the schedule table.
Any help will be very much appreciated. Thanks
I suggest you are approaching the problem backwards.
Devise several rules. Code the rules in your app, not in SQL. When inserting an event, pre-fill a calendar through the next 12 months with all occurrences of the event. Every month, go through all events and extend the "pre-fill" through another month (13 months hence).
Now the SELECTs are simple and fast.
SELECT ... WHERE date = '...'
has all the events for that day (assuming it is within 12 months).
The complexity is on inserting. But presumably you insert less often than you select.
The table with the event definitions would be only as complex as needed for your app to figure out what to do. Perhaps
start_date DATE,
frequency ENUM('day', 'week', 'month', ...)
multiplier TINYINT, -- this lets you say "every second week"
offset TINYINT, -- to get "15th of every month"
Twice a week would be two entries.
Better yet, there are several packages (in Perl, shell, etc) that provide a very rich language for expressing event-date-patterns. Furthermore, you may be able to simply 'call' it to do all the work for you!
I'm busy creating a personal mobile web app for home management.
Each day a READING is entered into a table, along with the days DATE.
One reading per day, meaning DATE is unique. READING could be the same, by very unlikely, if there is no usage for that day.
A usage amount for the day is calculated, by subtracting the previous days reading from the newly input reading.
How would I calculate the average usage numbers for a particular month?
Should the usage amount, once calculated, perhaps be stored back to the newly added row? Leaving for easy use of this to find an average?
Should a separate primary key be added, numbering the records, as apposed to using date to calculate the latest record added?
Thank you in advance, any help appreciated
Final solution:
When adding the latest readings, calculate day usage using previous record (found by using date). Add this to a third column.
To find daily average for current month, use MySQL avg, and limit to current year, and current month.
First - thanks for your time. My issue lies in my new usage of Access for tracking values from weekly excel reports. Each week I'm given a new excel file with updated values for about 50 employees. These values generally track their performance over 6 different metrics. I've begun to link these excels into an access database to keep and track that data each week. These linked tables are given the name convention of the date that the data is as of - example: 05-05; 05-12; 05-19, 05-26; etc.
My question is - is there a way to build a query to track the change (difference in values) from last week to this week (05-19 to 05-26), automatically? And also taking into account future additions of linked tables so that I don't have to add a piece to the query each week?
In addition, I'm looking to track overall change - first table 05-05 to the most recent linked table (which ever date that's true for, whether it's the end of July, or the end of the year).
Based on these 2 results, I'd eventually build out the query to show every week with their value and in the next column the week over week change (up down or neutral)