Value Comparison in InRule
Data comparison in InRule performs “implicit casting”.
If both operands are strings, then a simple string comparison will be performed.
Otherwise, if either of the operands are not strings, InRule implicitly casts both operands to a decimal data type for the comparison.
For example, in the case of date comparison (date A < date B), since both operands are not strings, it will cast both to decimals and then do the comparison.
If the data in these fields are:
Date A: null
Date B: 10/10/2010
Date A < date B evaluates to True, because date A being null makes its decimal value 0. Dates are represented as decimals by calculating the number of days from the origin date of Jan 2, 0001.
A null date becomes the origin date and therefore receives a decimal value of 0.