24. Calculate Date Difference

note the scenario below uses data from the deselect demo data package see docid 5 cozdtg0nwmlmeufrmbz scenario you have a data extension (orders) that contains a column with order dates and you want to add a new field to your target data extension that calculates the number of days between the order date and the current date note this scenario uses the feature custom values, which is available in deselect plus and advanced 1\ input on the overview of selections screen, click on new selection to create a new one drag data extension deselect demo orders to the selected data extensions section 2\ output hit the create data extension button, enter a name, e g orders target, and press save select the following fields by either double clicking on them or dragging them to the section on the right customerid, order date from deselect demo orders click save data extension now we're going to add a custom value under custom values on the left, click add new value under name, enter days since order and hit next choose type apply formula to a field choose type date difference a modal appears where you can do the setting add the first date under date 1 , make sure the field option is selected under data extension select deselect demo orders under field select order date add the second date under date 1 , make sure the timestamp option is selected select date select day in the express difference in drop down list hit save the logic defined above will, for each row, calculate the difference between the value of the order date column and the current date in days and return the result now that the custom value days since order has been created, we can map it to the target data extension fields click the gear icon > edit target data extension fields drag and dropping days since order from custom values to the target data extension fields 3\ preview when you click run preview on the preview screen, a results table will be shown with fields customerid and order date from deselect demo orders days since order, populated with the number of days between the date of the order date field and the current date