I store dates in a core data entity
attribute, I then display the date in
the table cells. I want to group all
the cells according to months and only
display the relevant dates in the
correct sections.
I'm using sectionNameKeyPath of the
NSFetchedResultsController, but I need
to only use the month in the date to
group. How can I achieve this? Would I
need to create a new attribute and
store just the month as a string or
can I use NSPredicate?
Please can anyone let me know if they
have done this or give me some
examples.
Thanks
Step one, make sure you have a Managed Object Class in your project that represents the core data entity that stores the date. Step two, in the implementation file for this entity, write a method that returns the month for that object. It should look at the date variable and use NSDateComponents methods to determine the month. You need not create a new attribute for it. Step three, when you initialize your NSFetchedResultsController, pass the name of the method that returns the month as the sectionNameKeyPath parameter. What you are essentially doing is creating a "getMonth" method that programmatically determines the month, and giving the value returned by that to the sectionNameKeyPath. I hope this is clear. Please ask for clarification if not.
Note. Make sure your month method returns the month in a way that sorts in the proper order (ie not alphabetically), and that your Table View translates that into a meaningful string.
Apple has a really great sample showing exactly how you can achieve this. I think it is what you are looking for.
Check out: http://developer.apple.com/library/ios/#samplecode/DateSectionTitles/Introduction/Intro.html#//apple_ref/doc/uid/DTS40009939
Related
I'm already struggling for days to use dates from excel in a proper way in anylogic..
I've created a database in where the date is formulated as integers in different columns since otherwise excel is messing up the dates (for example year=2021 , month=12 day=5 hour=6 minute=44 second=0 stands for 2021/12/5 6:44:00)
Now I know this can be converted to a date by the function toDate(year, month, day, hour, minutes seconds). But how can I use this integers to create agent with specific parameters from the database in a source and add to a custom population?
The most simple way is to add a column where the function toDate(......) is added in the database but I do not know how to do this (see picture if it is unclear). Or are there other solutions?
One way: use Dynamic Events.
Create one and in the action code, write mySource.inject(1)
In Main, on startup, load all dbase rows and create a DE for each row, below assuming it is only with an hour-column:
(Use the database query wizard to adjust your query).
In your source object, set it to "call of inject() function"
This will work, but it is quite cumbersome, as you can see. Much easier if you get your Excel right and just import the date column clean and well so you can use the Source option "arrival table in database" directly. I know you need regular arrivals, so maybe code that up in Excel to give you these on specific dates...
I am using Microsoft Access 2016. I am trying to find out how many years exist from the current year until a future year. I have a column that is end_date. I am trying to create a calculated field that is essentially YEAR(end_date) - YEAR(current_year). I tried to use YEAR(DATE()) but DATE() is not allowed to be used in a calculated field apparently.
Is there no way to do a calculation like this?
Nope. Calculated fields are cached and static, so are NEVER allowed to contain ANY information that will change over time, due to system settings, or anything else that is not directly entered in that row.
However, you should not be using calculated fields anyway. See http://allenbrowne.com/casu-14.html, among many posts advocating for not using calculated fields.
Instead, use queries to do calculations. That way, you won't have any trouble using the current date, and won't have to deal with the possible errors and portability issues calculated fields come with.
I changed my thinking to calculate this in a form. It does not seem good practice to have a field in a DB that changes everyday.
In a form, you can use this expression as controlsource for a textbox:
=DateDiff("yyyy",Date(),[EndDate])
However, that return the difference in calendar years. To find the count of full years, use a function like AgeSimple and this expression:
=AgeSimple([EndDate])
I am relatively new to using Crystal Reports. I am pulling the correct information from my database however I need to only pull the information from the beginning of the month to the current date, i.e. 09/01/2013 - 09/23/2013. Could anyone give me a snipit of code on how that would look.
Much appreciated.
The best way is you need to filter the data before it is populated on reports i.e. filtering the query itself. The other option is to create new parameter for the selected field and passing the value on runtime.
http://www.codeproject.com/Articles/205398/Crystal-Report-Filtering-Using-Selection-Parameter
In below figure you can add the records selection on the required field and add the condition similarly
I have a fairly simple problem, but I don't think I understand SSRS and scopes well enough to figure this out.
What I have is a case (one entity) that can have multiple appointments (another entity). Appointments have a date and a status. I want to display the next soonest appointment date and its status. To display the date I'm using
=Min(IIf(Fields!appt_start.Value > Globals!ExecutionTime, Fields!appt_start.Value, Nothing))
The idea is that I first pick only those appointments that occur in the future, and then grab the soonest one. It seems to work great.
Now, I need to apply the same filtering logic, but display the appointment status rather than the date. From my understanding, this is where scopes would come in. I could limit my scope to just the appointment I want, and then show its status. But I don't understand how to do that.
One way to go about this particular problem would be to use a filter in combination with the First function. Add a filter to the table to only show dates greater than the current day. Use a table row with no grouping and use expressions like this:
=First(Fields!appt_start.Value)
=First(Fields!appt_status.Value)
Another option would be to add calculated fields to the dataset to only populate values such as status when the date is greater than the current day. This is useful if you need to show more information later on.
Edit: Yes, you would want to sort the data by date for the First function to work right. You can actually filter at 3 different levels in SSRS. Right-click on your dataset and go to Dataset Properties. Click on Filters. Click Add. Fill in the expression, operator, and value to meet your need. You can also do this in the group properties or the table properties.
Do you know how to get the last non-empty value using mdx query.. then after that.. i want to count how many null values are next to it up to the last date. My main purpose for this is to count how many days a customer has no transaction..
i have to make a report in ssrs (using adventure works cube) that counts how many days a customer has no transaction..
thanks..
Use this article to obtain set of non empty dates.
To obtain count you can:
Use member properties (day of year or something more suitable in
this case) and just subtract one value from another.
You can find
last date with non empty value, previous one using LAG(1), include
them to the next construction {prev.date:last.date} and use COUNT
for set
Recently I follow this article, It really helps me.
The most important part is to understand scope usage.
Even If you don't have an Enterprise Edition, you can use it.