How to query for 'task' records by date - ios

Question

We are trying to make a app that keeps a users schedule. He wants a simple tableview to display a different section for each day and he wants all the tasks for that day to display in order. Here is the db schema im using:
TASK_ID , TASK_NAME(STRING), TASK_DURRATION(AMOUNT OF TIME IN MILI), TASK_START_TSTAMP(EPOCH TIMESTAMP), TASK_END_TSTAMP(EPOCH TIMESTAMP), TASK_COMPLETED(BOOL)
How would I begin to go about querying for tasks by day? Like if i wanted to return all the tasks for the next 7 days.
I have to :
•Allow users to create tasks with a specific duration and in some cases a specific start time
•Query for the next 7 days worth of tasks chunked by date.
So what do I do? Find a way to get a array of the next 7 days, loop through and run a query for each one for all the tasks scheduled on that day?

Answer 1

You want to calculate startDate and endDate to be used in your SQL using calendrical calculations of NSCalendar.
Let's say it's 3:24pm on January 20th, and you want all tasks in the next seven days, up to 3:24pm on January 27th, you could do something like:
let startDate = NSDate()
let endDate = NSCalendar.currentCalendar().dateByAddingUnit(.Day, value: 7, toDate: startDate, options: [])!
Then build your query using those start and end dates.
If, however, you want all events scheduled anytime on January 20th through January 26th (inclusive), you could use something like:
let calendar = NSCalendar.currentCalendar()
let components = calendar.components([.Day, .Month, .Year], fromDate: NSDate())
let startDate = calendar.dateFromComponents(components)!
let endDate = calendar.dateByAddingUnit(.Day, value: 7, toDate: startDate, options: [])!
Then you could build your SQL using startDate and endDate, if you're storing those as UNIX epoch double values:
let sql = "select * from TASKS where TASK_START_TSTAMP >= \(startDate.timeIntervalSince1970) and TASK_START_TSTAMP < \(endDate.timeIntervalSince1970)"