SQL Server : get next relative day of week. (Next Monday, Tuesday, Wed…)

Question

What I need is a date for the next given day (Monday, Tuesday, Wed...) following today\'s date.

The user is allowed to select what day following they want and that i

Answer 1

A calendar table is an alternative to using a bunch of date functions and date arithmetic. A minimal calendar table for this particular problem might look something like this.

2013-09-20  Fri
2012-09-21  Sat
2012-09-22  Sun
2012-09-23  Mon
2012-09-24  Tue
...

So a query to get the next Monday might look like this.

select min(cal_date)
from calendar
where cal_date > current_date
  and day_of_week = 'Mon';

In practice, you'll probably want a lot more columns in the calendar table, because you'll find a lot of uses for it.

Also, code that uses a calendar table can usually be seen to be obviously correct. Reading the code above is simple: select the minimum calendar date that's after today and that falls on Monday. It's pretty rare to see code that relies on date functions and date arithmetic that's obviously correct.

A calendar table in PostgreSQL