Why does the expression date('mm/dd/yyyy')>='mm/dd/yyyy' work independently of the format?

[julioarriaga]

Hi everyone,

Thank you in advance for your time in answering this question.

How does QV know how to apply a criteria of '>=' to a date string independently of the formats? As these are basically different strings (image 1 and 2), shouldn't they give different results?

P.S. I know date is a formatting function but still the script registers it as a string.

image 1

Image 2

[sunny_talwar]

What is the difference between the two images? Also, your date format should be DD/MM/YYYY and not 30/08/2017

[julioarriaga]

Sorry, my bad, I just corrected the post

[sunny_talwar]

Why would you expect to get different results? You are using same date in two formats? Personally, I prefer to use MakeDate() function when do comparisons with date field

Where Bill_Date >= MakeDate(2017, 8, 30);

[rwunderlich · Accepted solution]

The simple answer is that Dates are not strings, they are Dual type. They have both a numeric value (the number of days since Dec 30, 1899) and a formatted string representation.  QV is smart enough to use either the numeric or string format depending on the context.  For example, when you do a comparison expression, the numeric value is used.  When you put the field in a listbox, the string is used.

-Rob

http://masterssummit.com

http://qlikviewcookbook.com