Through the use of the DayName function, we can display the day name of the week for a particular date.
Today is Monday 13th February 2012.
What would be the result of creating the following formula in WebIntelligence?
=DayName(CurrentDate())
The answer is Monday. Today is Monday 13th February 2012.
Now, if I wanted to display the previous working day, I couldn’t use the RelativeDate function on it’s own. Remember we are looking for previous working day and not previous day.
In order to do this, we need to check the current day and determine if the previous day is a weekend. If it is, we need to adjust the output accordingly.
We can develop this logic within WebIntelligence using a nested IF statement.
Let’s work through an example:
Create a new WebIntelligence report. If you have a CurrentDate object in your universe, we can use that. If you don’t, then bring back any object (preferably one that doesn’t bring back many rows – we don’t actually want to use that value, but we do want to end up with a table).
If you do not have a CurrentDate object, create the following formula in WebIntelligence:
=CurrentDate()
Note that the format of the date value returned depends on how the universe object has been set up or how your WebIntelligence setup is configured. In some cases it may be formatted as dd-Mmm-yyy or dd/mm/yyyy. If you want to use a specific format and you are using the =CurrentDate() formula in WebIntelligence, you can format the date using:
=FormatDate(CurrentDate();”dd-Mmm-yyyy”)
For the purposes of this article however, we will be using the default format.
Add a second column to your table. We will call this column ‘Current Day Name’ and we will use the DayName function to return the day of the week:
=DayName(CurrentDate())
Now to get the previous working date.
We need to check the value (Day Name) of the current date. If it is a Tuesday, Wednesday, Thursday, Friday or Saturday, we will be fine using the RelativeDate function, as the previous day to the above listed days is a working day. (I’m ignoring Bank Holidays, Festive Days, etc. That’s for a future topic!)
However, if we find that the current Day Name is a Sunday or a Monday, then using RelativeDate is going to retrieve a weekend day. We need to handle these two scenarios using a nested IF statement.
The statement is built up as follows:
If the current day name is a Monday, then subtract three days from the current date
If the current day name is a Sunday, then subtract two days from the current date
The formula is made up as follows:
=If(DayName(CurrentDate())=”Monday”;RelativeDate(CurrentDate();-3);If(DayName(CurrentDate())=”Sunday”;RelativeDate(CurrentDate();-2);RelativeDate(CurrentDate();-1)))
Lets break down this formula.
An IF expression has three components:
If(boolean_expr;value if true;value if false)
The boolean_expr part is the statement that we test.
In our case, we want to check if the CurrentDate() is a Monday.
If it is true that it is a Monday, we want to use the RelativeDate function to subtract 3 days from the CurrentDate().
If it is false, i.e. the current date is not a Monday, we need to perform a further check. This requires a second IF statement to perform this second check.
The second check asks if the CurrentDate() is a Sunday.
If it is true that it is a Sunday, we want to use the RelativeDate function to subtract 2 days from the CurrentDate().
If it is false, i.e. the current date is not a Sunday, and we know its not a Monday as we checked for that previously, then we know that the day is a Tuesday, Wednesday, Thursday, Friday or Saturday and hence we can safely use RelativeDate with a value of -1 to give us the previous working day.
The formula above displays the result in a date format. If we wanted to display the result as a Day Name only, we can tweak the formula a little to incorporate the DayName() function:
=If(DayName(CurrentDate())=”Monday”;DayName(RelativeDate(CurrentDate();-3));If(DayName(CurrentDate())=”Sunday”;DayName(RelativeDate(CurrentDate();-2));DayName(RelativeDate(CurrentDate();-1))))
So using this formula we should end up with the following result:
Current Day Previous Working Day
Monday Friday
Tuesday Monday
Wednesday Tuesday
Thursday Wednesday
Friday Thursday
Saturday Friday
Sunday Friday
